Learning english 80 essays
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>01 The Language of Music
A painter hangs his or her finished picture on a wall, and everyone can see it. A
composer writes a work, but no one can hear it until it is performed. Professional singers
and players have great responsibilities, for the composer is utterly dependent on them. A
student of music needs as long and as arduous a training to become a performer as a
medical student needs to become a doctor. Most training is concerned with technique,
for musicians have to have the muscular proficiency of an athlete or a ballet dancer.
Singers practice breathing every day, as their vocal chords would be inadequate without
controlled muscular support. String players practice moving the fingers of the left hand
up and down, while drawing the bow to and fro with the right arm --two entirely
different movements.
Singers and instrumentalists have to be able to get every note perfectly in tune.
Pianists are spared this particular anxiety, for the notes are already there, waiting for
them, and it is the piano tuner's responsibility to tune the instrument for them. But they
have their own difficulties: the hammers that hit the strings have to be coaxed not to
sound like percussion, and each overlapping tone has to sound clear.
This problem of getting clear texture is one that confronts student conductors: they
have to learn to know every note of the music and how it should sound, and they have to
aim at controlling these sounds with fanatical but selfless authority.
Technique is of no use unless it is combined with musical knowledge and
understanding. Great artists are those who are so thoroughly at home in the language of
music that they can enjoy performing works written in any century.
>02 Schooling and Education
It is commonly believed in the United States that school is where people go to get an
education. Nevertheless, it has been said that today children interrupt their education to
go to school. The distinction between schooling and education implied by this remark is
important.
Education is much more open-ended and all-inclusive than schooling. Education
knows no bounds. It can take place anywhere, whether in the shower or in the job,
whether in a kitchen or on a tractor. It includes both the formal learning that takes place
in schools and the whole universe of informal learning. The agents of education can range
from a revered grandparent to the people debating politics on the radio, from a child to a
distinguished scientist.
Whereas schooling has a certain predictability, education quite often produces
surprises. A chance conversation with a stranger may lead a person to discover how little
is known of other religions. People are engaged in education from infancy on. Education,
then, is a very broad, inclusive term. It is a lifelong process, a process that starts long
before the start of school, and one that should be an integral part of one's entire life.
Schooling, on the other hand, is a specific, formalized process, whose general
pattern varies little from one setting to the next. Throughout a country, children arrive at
school at approximately the same time, take assigned seats, are taught by an adult, use
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similar textbooks, do homework, take exams, and so on. The slices of reality that are to
be learned, whether they are the alphabet or an understanding of the workings of
government, have usually been limited by the boundaries of the subject being taught.
For example, high school students know that they are not likely to find out in their
classes the truth about political problems in their communities or what the newest
filmmakers are experimenting with. There are definite conditions surrounding the
formalized process of schooling.
>03 The Definition of "Price"
Prices determine how resources are to be used. They are also the means by which
products and services that are in limited supply are rationed among buyers. The price
system of the United States is a complex network composed of the prices of all the
products bought and sold in the economy as well as those of a myriad of services,
including labor, professional, transportation, and public-utility services. The
interrelationships of all these prices make up the "system" of prices. The price of any
particular product or service is linked to a broad, complicated system of prices in which
everything seems to depend more or less upon everything else. If one were to ask a
group of randomly selected individuals to define "price", many would reply that price is
an amount of money paid by the buyer to the seller of a product or service or, in other
words, that price is the money value of a product or service as agreed upon in a market
transaction. This definition is, of course, valid as far as it goes. For a complete
understanding of a price in any particular transaction, much more than the amount of
money involved must be known. Both the buyer and the seller should be familiar with
not only the money amount, but with the amount and quality of the product or service to
be exchanged, the time and place at which the exchange will take place and payment will
be made, the form of money to be used, the credit terms and discounts that apply to the
transaction, guarantees on the product or service, delivery terms, return privileges, and
other factors. In other words, both buyer and seller should be fully aware of all the
factors that comprise the total "package" being exchanged for the asked-for amount of
money in order that they may evaluate a given price.
>04 Electricity
The modern age is an age of electricity. People are so used to electric lights, radio,
televisions, and telephones that it is hard to imagine what life would be like without
them. When there is a power failure, people grope about in flickering candlelight, cars
hesitate in the streets because there are no traffic lights to guide them, and food spoils in
silent refrigerators.
Yet, people began to understand how electricity works only a little more than two
centuries
ago. Nature has apparently been experimenting in this field for millions of years.
Scientists are discovering more and more that the living world may hold many
interesting secrets of electricity that could benefit humanity.
All living cells send out tiny pulses of electricity. As the heart beats, it sends out
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pulses of record; they form an electrocardiogram, which a doctor can study to
determine how well the heart is working. The brain, too, sends out brain waves of
electricity, which can be recorded in an electroencephalogram. The electric currents
generated by most living cells are extremely small -- often so small that sensitive
instruments are needed to record them. But in some animals, certain muscle cells have
become so specialized as electrical generators that they do not work as muscle cells at
all. When large numbers of these cells are linked together, the effects can be
astonishing.
The electric eel is an amazing storage battery. It can send a jolt of as much as eight
hundred volts of electricity through the water in which it lives. (An electric house
current is only one hundred twenty volts.) As many as four-fifths of all the cells in the
electric eel's body are specialized for generating electricity, and the strength of the
shock it can deliver corresponds roughly to the length of its body.
>05 The Beginning of Drama
There are many theories about the beginning of drama in ancient Greece. The one
most widely accepted today is based on the assumption that drama evolved from ritual.
The argument for this view goes as follows. In the beginning, human beings viewed the
natural forces of the world - even the seasonal changes - as unpredictable, and they
sought through various means to control these unknown and feared powers. Those
measures which appeared to bring the desired results were then retained and repeated
until they hardened into fixed rituals. Eventually stories arose which explained or
veiled the mysteries of the rites. As time passed some rituals were abandoned, but the
stories, later called myths, persisted and provided material for art and drama.
Those who believe that drama evolved out of ritual also argue that those rites
contained the seed of theater because music, dance, masks, and costumes were almost
always used. Furthermore, a suitable site had to be provided for performances and
when the entire community
did not participate, a clear division was usually made between the "acting area" and the
"auditorium." In addition, there were performers, and, since considerable importance
was attached to avoiding mistakes in the enactment of rites, religious leaders usually
assumed that task. Wearing masks and costumes, they often impersonated other people,
animals, or supernatural beings, and mimed the desired effect -- success in hunt or battle,
the coming rain, the revival of the Sun -- as an actor might. Eventually such dramatic
representations were separated from religious activities.
Another theory traces the theater's origin from the human interest in storytelling.
According to this view tales (about the hunt, war, or other feats) are gradually elaborated,
at first through the use of impersonation, action, and dialogue by a narrator and then
through the assumption of each of the roles by a different person. A closely related
theory traces theater to those dances that are primarily rhythmical and gymnastic or that
are imitations of animal movements and sounds.
>06 Television
Television -- the most pervasive and persuasive of modern technologies, marked by
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rapid change and growth -- is moving into a new era, an era of extraordinary
sophistication and versatility, which promises to reshape our lives and our world. It is an
electronic revolution of sorts, made possible by the marriage of television and computer
technologies.
The word "television", derived from its Greek (tele: distant) and Latin (visio: sight)
roots, can literally be interpreted as sight from a distance. Very simply put, it works in
this way: through a sophisticated system of electronics, television provides the
capability of converting an image (focused on a special photoconductive plate within a
camera) into electronic impulses, which can be sent through a wire or cable. These
impulses, when fed into a receiver (television set), can then be electronically
reconstituted into that same image.
Television is more than just an electronic system, however. It is a means of expression,
as well as a vehicle for communication, and as such becomes a powerful tool for reaching
other human beings.
The field of television can be divided into two categories determined by its means of
transmission. First, there is broadcast television, which reaches the masses through
broad-based airwave transmission of television signals. Second, there is nonbroadcast
television, which provides for the needs of individuals or specific interest groups through
controlled transmission techniques.
Traditionally, television has been a medium of the masses. We are most familiar with
broadcast television because it has been with us for about thirty-seven years in a form similar
to what exists today. During those years, it has been controlled, for the most part, by the
broadcast networks, ABC, NBC, and CBS, who have been the major purveyors of news,
information, and entertainment. These giants of broadcasting have actually shaped not only
television but our perception of it as well. We have come to look upon the picture tube as a
source of entertainment, placing our role in this dynamic medium as the passive viewer
>07 Andrew Carnegie
Andrew Carnegie, known as the King of Steel, built the steel industry in the United States,
and, in the process, became one of the wealthiest men in America. His success resulted in
part from his ability to sell the product and in part from his policy of expanding during
periods of economic decline, when most of his competitors were reducing their
investments.
Carnegie believed that individuals should progress through hard work, but he also felt
strongly that the wealthy should use their fortunes for the benefit of society. He opposed
charity, preferring instead to provide educational opportunities that would allow others to
help themselves. “He who dies rich, dies disgraced,” he often said.
Among his more noteworthy contributions to society are those that bear his name,
including
the Carnegie Institute of Pittsburgh, which has a library, a museum of fine arts, and a
museum of national history. He also founded a school of technology that is now part of
Carnegie-Mellon University. Other philanthropic gifts are the Carnegie Endowment for
International Peace to promote understanding between nations, the Carnegie Institute of
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Washington to fund scientific research, and Carnegie Hall to provide a center for the
arts.
Few Americans have been left untouched by Andrew Carnegie's generosity. His
contributions of more than five million dollars established 2,500 libraries in small
communities throughout the country and formed the nucleus of the public library system
that we all enjoy today.
>08 American Revolution
The American Revolution was not a revolution in the sense of a radical or total
change. It was not a sudden and violent overturning of the political and social
framework, such as later occurred in France and Russia, when both were already
independent nations. Significant changes were ushered in, but they were not
breathtaking. What happened was accelerated evolution rather than outright revolution.
During the conflict itself people went on working and praying, marrying and playing.
Most of them were not seriously disturbed by the actual fighting, and many of the more
isolated communities scarcely knew that a war was on. America's War of Independence
heralded the birth of three modern nations. One was Canada, which received its first
large influx of English-speaking population from the thousands of loyalists who fled
there from the United States. Another was Australia, which became a penal colony now
that America was no longer available for prisoners and debtors. The third newcomer --
the United States --based itself squarely on republican principles.
Yet even the political overturn was not so revolutionary as one might suppose. In
some states, notably Connecticut and Rhode Island, the war largely ratified a colonial
self-rule already existing. British officials, everywhere ousted, were replaced by a
home-grown governing class, which promptly sought a local substitute for king and
Parliament.
>09 Suburbanization
If by "suburb" is meant an urban margin that grows more rapidly than its already
developed interior, the process of suburbanization began during the emergence of the
industrial city in the second quarter of the nineteenth century. Before that period the city
was a small highly compact cluster in which people moved about on foot and goods were
conveyed by horse and cart. But the early factories built in the 1830's and 1840’s were
located along waterways and near railheads at the edges of cities, and housing was
needed for the thousands of people drawn by the prospect of employment. In time, the
factories were surrounded by proliferating mill towns of apartments and row houses that
abutted the older, main cities. As a defense against this encroachment and to enlarge
their tax bases, the cities appropriated their industrial neighbors. In 1854, for example,
the city of Philadelphia annexed most of Philadelphia County. Similar municipal
maneuvers took place in Chicago and in New York. Indeed, most great cities of the
United States achieved such status only by incorporating the communities along their
borders.
With the acceleration of industrial growth came acute urban crowding and
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accompanying social stress -- conditions that began to approach disastrous proportions
when, in 1888, the first commercially successful electric traction line was developed.
Within a few years the horse-drawn trolleys were retired and electric streetcar networks
crisscrossed and connected every major urban area, fostering a wave of suburbanization
that transformed the compact industrial city into a dispersed metropolis. This first phase
of mass-scale suburbanization was reinforced by the simultaneous emergence of the
urban Middle Class, whose desires for homeownership in neighborhoods far from the
aging inner city were satisfied by the developers of single-family housing tracts.
>10 Types of Speech
Standard usage includes those words and expressions understood, used, and
accepted by a majority of the speakers of a language in any situation regardless of the
level of formality. As such, these words and expressions are well defined and listed in
standard dictionaries. Colloquialisms, on the other hand, are familiar words and idioms
that are understood by almost all speakers of a language and used in informal speech or
writing, but not considered appropriate for more formal situations. Almost all idiomatic
expressions are colloquial language. Slang, however, refers to words and expressions
understood by a large number of speakers but not accepted as good, formal usage by the
majority. Colloquial expressions and even slang may be found in standard dictionaries
but will be so identified. Both colloquial usage and slang are more common in speech
than in writing.
Colloquial speech often passes into standard speech. Some slang also passes into
standard speech, but other slang expressions enjoy momentary popularity followed by
obscurity. In some cases, the majority never accepts certain slang phrases but
nevertheless retains them in their collective memories. Every generation seems to
require its own set of words to describe familiar objects and events.
It has been pointed out by a number of linguists that three cultural conditions are
necessary for the creation of a large body of slang expressions. First, the introduction
and acceptance of new objects and situations in the society; second, a diverse population
with a large number of subgroups; third, association among the subgroups and the
majority population.
Finally, it is worth noting that the terms "standard" "colloquial" and "slang" exist
only as abstract labels for scholars who study language. Only a tiny number of the
speakers of any language will be aware that they are using colloquial or slang
expressions. Most speakers of English will, during appropriate situations, select and use
all three types of expressions.
>11 Archaeology
Archaeology is a source of history, not just a humble auxiliary discipline.
Archaeological data are historical documents in their own right, not mere illustrations to
written texts. Just as much as any other historian, an archaeologist studies and tries to
reconstitute the process that has created the human world in which we live -- and us
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ourselves in so far as we are each creatures of our age and social environment.
Archaeological data are all changes in the material world resulting from human action or,
more succinctly, the fossilized results of human behavior. The sum total of these
constitutes what may be called the archaeological record. This record exhibits certain
peculiarities and deficiencies the consequences of which produce a rather superficial
contrast between archaeological history and the more familiar kind based upon written
records.
Not all human behavior fossilizes. The words I utter and you hear as vibrations in the
air are certainly human changes in the material world and may be of great historical
significance. Yet they leave no sort of trace in the archaeological records unless they are
captured by a dictaphone or written down by a clerk. The movement of troops on the
battlefield may "change the course of history," but this is equally ephemeral from the
archaeologist's standpoint. What is perhaps worse is that most organic materials are
perishable. Everything made of wood, hide, wool, linen, grass, hair, and similar
materials will decay and vanish in dust in a few years or centuries, save under very
exceptional conditions. In a relatively brief period the archaeological record is reduced
to mere scraps of stone, bone, glass, metal, and earthenware. Still modern archaeology,
by applying appropriate techniques and comparative methods, aided by a few lucky
finds from peat-bogs, deserts, and frozen soils, is able to fill up a good deal of the gap.
> 12 Mu s eu ms
From Boston to Los Angeles, from New York City to Chicago to Dallas, museums
are either planning, building, or wrapping up wholesale expansion programs. These
programs already have radically altered facades and floor plans or are expected to do so
in the not-too-distant future.
In New York City alone, six major institutions have spread up and out into the air
space and neighborhoods around them or are preparing to do so.
The reasons for this confluence of activity are complex, but one factor is a
consideration everywhere -- space. With collections expanding, with the needs and
functions of museums changing, empty space has become a very precious commodity.
Probably nowhere in the country is this more true than at the Philadelphia Museum
of Art, which has needed additional space for decades and which received its last
significant facelift ten years ago. Because of the space crunch, the Art Museum has
become increasingly cautious in considering acquisitions and donations of art, in some
cases passing up opportunities to strengthen its collections.
Deaccession -- or selling off -- works of art has taken on new importance because of
the museum's space problems. And increasingly, curators have been forced to juggle
gallery space, rotating one masterpiece into public view while another is sent to storage.
Despite the clear need for additional gallery and storage space, however, "the
museum has no plan, no plan to break out of its envelope in the next fifteen years,"
according to Philadelphia Museum of Art's president.
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> 1 3 S ky s c ra p er s a nd E n v i ro nme n t
In the late 1960's, many people in North America turned their attention to
environmental problems, and new steel-and-glass skyscrapers were widely criticized.
Ecologists pointed out that a cluster of tall buildings in a city often overburdens public
transportation and parking lot capacities.
Skyscrapers are also lavish consumers, and wasters, of electric power. In one recent
year, the addition of 17 million square feet of skyscraper office space in New York
City raised the peak daily demand for electricity by 120, 000 kilowatts -- enough to
supply the entire city of Albany, New York, for a day.
Glass-walled skyscrapers can be especially wasteful. The heat loss (or gain) through
a wall of half-inch plate glass is more than ten times that through a typical masonry
wall filled with insulation board. To lessen the strain on heating and air-conditioning
equipment, builders of skyscrapers have begun to use double-glazed panels of glass,
and reflective glasses coated with silver or gold mirror films that reduce glare as well
as heat gain. However, mirror-walled skyscrapers raise the temperature of the
surrounding air and affect neighboring buildings.
Skyscrapers put a severe strain on a city's sanitation facilities, too. If fully occupied,
the two World Trade Center towers in New York City would alone generate 2.25
million gallons of raw sewage each year -- as much as a city the size of Stanford,
Connecticut, which has a population of more than 109, 000.
>14 A Rare Fossil Record
The preservation of embryos and juveniles is a rate occurrence in the fossil record.
The tiny, delicate skeletons are usually scattered by scavengers or destroyed by
weathering before they can be fossilized. Ichthyosaurs had a higher chance of being
preserved than did terrestrial creatures because, as marine animals, they tended to live
in environments less subject to erosion. Still, their fossilization required a suite of
factors: a slow rate of decay of soft tissues, little scavenging by other animals, a lack of
swift currents and waves to jumble and carry away small bones, and fairly rapid burial.
Given these factors, some areas have become a treasury of well-preserved ichthyosaur
fossils.
The deposits at Holzmaden, Germany, present an interesting case for analysis. The
ichthyosaur remains are found in black, bituminous marine shales deposited about 190
million years ago. Over the years, thousands of specimens of marine reptiles, fish and
invertebrates have been recovered from these rocks. The quality of preservation is
outstanding, but what is even more impressive is the number of ichthyosaur fossils
containing preserved embryos.
Ichthyosaurs with embryos have been reported from 6 different levels of the shale in a
small area around Holzmaden, suggesting that a specific site was used by large numbers
of ichthyosaurs repeatedly over time. The embryos are quite advanced in their physical
development; their paddles, for example, are already well formed. One specimen is even
preserved in the birth canal. In addition, the shale contains the remains of many
newborns that are between 20 and 30 inches long.
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Why are there so many pregnant females and young at Holzmaden when they are so
rare elsewhere? The quality of preservation is almost unmatched and quarry operations
have been carried out carefully with an awareness of the value of the fossils. But these
factors do not account for the interesting question of how there came to be such a
concentration of pregnant ichthyosaurs in a particular place very close to their time of
giving birth.
>15 The Nobe l Academy
For the last 82 years, Sweden's Nobel Academy has decided who will receive the
Nobel Prize in Literature, thereby determining who will be elevated from the great and
the near great to the immortal. But today the Academy is coming under heavy criticism
both from the without and from within. Critics contend that the selection of the winners
often has less to do with true writing ability than with the peculiar internal politics of the
Academy and of Sweden itself. According to Ingmar Bjorksten, the cultural editor for
one of the country's two major newspapers, the prize continues to represent "what
people call a very Swedish exercise: reflecting Swedish tastes." The Academy has
defended itself against such charges of provincialism in its selection by asserting that its
physical distance from the great literary capitals of the world actually serves to protect
the Academy from outside influences. This may well be true, but critics respond that this
very distance may also be responsible for the Academy's inability to perceive accurately
authentic trends in the literary world.
Regardless of concerns over the selection process, however, it seems that the prize
will continue to survive both as an indicator of the literature that we most highly praise,
and as an elusive goal that writers seek. If for no other reason, the prize will continue to
be desirable for the financial rewards that accompany it; not only is the cash prize itself
considerable, but it also dramatically increases sales of an author's books.
>16 The War between Britain and France
In the late eighteenth century, battles raged in almost every corner of Europe, as well
as in the Middle East, South Africa, the West Indies, and Latin America. In reality,
however, there was only one major war during this time, the war between Britain and
France. All other battles were ancillary to this larger conflict, and were often at least
partially related to its antagonists' goals and strategies. France sought total domination
of Europe. This goal was obstructed by British independence and Britain's efforts
throughout the continent to thwart Napoleon; through treaties, Britain built coalitions
(not dissimilar in concept to today's NATO) guaranteeing British participation in all
major European conflicts. These two antagonists were poorly matched, insofar as they
had very unequal strengths: France was predominant on land, Britain at sea. The French
knew that, short of defeating the British navy, their only hope of victory was to close all
the ports of Europe to British ships.
Accordingly, France set out to overcome Britain by extending its military
domination from Moscow to Lisbon, from Jutland to Calabria. All of this entailed
tremendous risk, because France did not have the military resources to control this much
territory and still protect itself and maintain order at home.
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French strategists calculated that a navy of 150 ships would provide the force
necessary to defeat the British navy. Such a force would give France a three-to-two
advantage over Britain. This advantage was deemed necessary because of Britain's
superior sea skills and technology, and also because Britain would be fighting a
defensive war, allowing it to win with fewer forces. Napoleon never lost sight of his goal,
because Britain represented the last substantial
impediment to his control of Europe. As his force neared that goal, Napoleon grew
increasingly impatient and began planning an immediate attack.
>17 Evolution of Sleep
Sleep is very ancient. In the electroencephalographic sense we share it with all the
primates and almost all the other mammals and birds: it may extend back as far as the
reptiles.
There is some evidence that the two types of sleep, dreaming and dreamless, depend
on the life-style of the animal, and that predators are statistically much more likely to
dream than prey, which are in turn much more likely to experience dreamless sleep. In
dream sleep, the animal is powerfully immobilized and remarkably unresponsive to
external stimuli. Dreamless sleep is much shallower, and we have all witnessed cats or
dogs cocking their ears to a sound when apparently fast asleep. The fact that deep dream
sleep is rare among prey today seems clearly to be a product of natural selection, and it
makes sense that today, when sleep is highly evolved, the stupid animals are less
frequently immobilized by deep sleep than the smart ones. But why should they sleep
deeply at all? Why should a state of such deep immobilization ever have evolved?
Perhaps one useful hint about the original function of sleep is to be found in the fact that
dolphins and whales and aquatic mammals in general seem to sleep very little. There is,
by and large, no place to hide in the ocean. Could it be that, rather than increasing an
animal's vulnerability, the function of sleep is to decrease it? Wilse Webb of the
University of Florida and Ray Meddis of London University have suggested this to be
the case. It is conceivable that animals that are too stupid to be quiet on their own
initiative are, during periods of high risk, immobilized by the implacable arm of sleep.
The point seems particularly clear for the young of predatory animals. This is an
interesting notion and probably at least partly true.
>18 Modern American Universities
Before the 1850's, the United States had a number of small colleges, most of them
dating from colonial days. They were small, church connected institutions whose
primary concern was to shape the moral character of their students.
Throughout Europe, institutions of higher learning had developed, bearing the
ancient name of university. In Germany a different kind of university had developed.
The German university was concerned primarily with creating and spreading
knowledge, not morals. Between mid-century and the end of the 1800's, more than nine
thousand young Americans, dissatisfied with their training at home, went to Germany
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for advanced study. Some of them returned to become presidents of venerable colleges
-- Harvard, Yale, and Columbia -- and transform them into modern universities. The
new presidents broke all ties with the churches and brought in a new kind of faculty.
Professors were hired for their knowledge of a subject, not because they were of the
proper faith and had a strong arm for disciplining students. The new principle was that
a university was to create knowledge as well as pass it on, and this called for a faculty
composed of teacher-scholars. Drilling and learning by rote were replaced by the
German method of lecturing, in which the professor's own research was presented in
class. Graduate training leading to the Ph.D., an ancient German degree signifying the
highest level of advanced scholarly attainment, was introduced. With the
establishment of the seminar system, graduate students learned to question, analyze,
and conduct their own research.
At the same time, the new university greatly expanded in size and course offerings,
breaking completely out of the old, constricted curriculum of mathematics, classics,
rhetoric, and music. The president of Harvard pioneered the elective system, by which
students were able to choose their own courses of study. The notion of major fields of
study emerged. The new goal was to make the university relevant to the real pursuits of
the world. Paying close heed to the practical needs of society, the new universities
trained men and women to work at its tasks, with engineering students being the most
characteristic of the new regime. Students were also trained as economists, architects,
agriculturalists, social welfare workers, and teachers.
>19 Children's Numerical Skills
People appear to be born to compute. The numerical skills of children develop so
early and so inexorably that it is easy to imagine an internal clock of mathematical
maturity guiding their growth. Not long after learning to walk and talk, they can set the
table with impressive accuracy -- one knife, one spoon, one fork, for each of the five
chairs. Soon they are capable of noting that they have placed five knives, spoons and
forks on the table and, a bit later, that this amounts to fifteen pieces of silverware.
Having thus mastered addition, they move on to subtraction. It seems almost reasonable
to expect that if a child were secluded on a desert island at birth and retrieved seven
years later, he or she could enter a second-grade mathematics class without any serious
problems of intellectual adjustment.
Of course, the truth is not so simple. This century, the work of cognitive
psychologists has illuminated the subtle forms of daily learning on which intellectual
progress depends. Children were observed as they slowly grasped -- or, as the case
might be, bumped into -- concepts that adults take for granted, as they refused, for
instance, to concede that quantity is unchanged as water pours from a short stout glass
into a tall thin one. Psychologists have since demonstrated that young children, asked to
count the pencils in a pile, readily report the number of blue or red pencils, but must be
coaxed into finding the total. Such studies have suggested that the rudiments of
mathematics are mastered gradually, and with effort. They have also suggested that the
very concept of abstract numbers - the idea of an oneness, a twoness, a threeness that
applies to any class of objects and is a prerequisite for doing anything more
mathematically demanding than setting a table - is itself far from innate.
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>20 The Historical Significance of American Revolution
The ways of history are so intricate and the motivations of human actions so
complex that it is always hazardous to attempt to represent events covering a number of
years, a multiplicity of persons, and distant localities as the expression of one
intellectual or social movement; yet the historical process which culminated in the
ascent of Thomas Jefferson to the presidency can be regarded as the outstanding
example not only of the birth of a new way of life but of nationalism as a new way of life.
The American Revolution represents the link between the seventeenth century, in which
modern England became conscious of itself, and the awakening of modern Europe at the
end of the eighteenth century. It may seem strange that the march of history should have
had to cross the Atlantic Ocean, but only in the North American colonies could a
struggle for civic liberty lead also to the foundation of a new nation.
Here, in the popular rising against a "tyrannical" government, the fruits were more
than the securing of a freer constitution. They included the growth of a nation born in
liberty by the will of the people, not from the roots of common descent, a geographic
entity, or the ambitions of king or dynasty. With the American nation, for the first time,
a nation was born, not in the dim past of history but before the eyes of the whole world.
>21 The Origin of Sports
When did sport begin? If sport is, in essence, play, the claim might be made that
sport is much older than humankind, for, as we all have observed, the beasts play. Dogs
and cats wrestle and play ball games. Fishes and birds dance. The apes have simple,
pleasurable games. Frolicking infants, school children playing tag, and adult arm
wrestlers are demonstrating strong, transgenerational and transspecies bonds with the
universe of animals - past, present, and future. Young animals, particularly, tumble,
chase, run, wrestle, mock, imitate, and laugh(or so it seems) to the point of delighted
exhaustion. Their play, and ours, appears to serve no other purpose than to give pleasure
to the players, and apparently, to remove us temporarily from the anguish of life in
earnest. Some philosophers have claimed that our playfulness is the most noble part of
our basic nature. In their generous conceptions, play harmlessly and experimentally
permits us to put our creative forces, fantasy, and imagination into action. Play is release
from the tedious battles against scarcity and decline which are the incessant, and
inevitable, tragedies of life. This is a grand conception that excites and provokes. The
holders of this view claim that the origins of our highest accomplishments - liturgy,
literature, and law - can be traced to a play impulse which, paradoxically, we see most
purely enjoyed by young beasts and children. Our sports, in this rather happy,
nonfatalistic view of human nature, are more splendid creations of the nondatable,
transspecies play impulse.
>22 Collectibles
Collectibles have been a part of almost every culture since ancient times. Whereas
some objects have been collected for their usefulness, others have been selected for their
aesthetic beauty alone. In the United States, the kinds of collectibles currently popular
range from traditional objects such as stamps, coins, rare books, and art to more recent
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items of interest like dolls, bottles, baseball cards, and comic books.
Interest in collectibles has increased enormously during the past decade, in part
because some collectibles have demonstrated their value as investments. Especially
during cycles of high inflation, investors try to purchase tangibles that will at least retain
their current market values. In general, the most traditional collectibles will be sought
because they have preserved their value over the years, there is an organized auction
market for them, and they are most easily sold in the event that cash is needed. Some
examples of the most stable collectibles are old masters, Chinese ceramics, stamps,
coins, rare books, antique jewelry, silver, porcelain, art by well-known artists,
autographs, and period furniture. Other items of more recent interest include old
photograph records, old magazines, post cards, baseball cards, art glass, dolls, classic
cars, old bottles, and comic books. These relatively new kinds of collectibles may
actually appreciate faster as short-term investments, but may not hold their value as
long-term investments. Once a collectible has had its initial play, it appreciates at a
fairly steady rate, supported by an increasing number of enthusiastic collectors
competing for the limited supply of collectibles that become increasingly more difficult
to locate.
>23 Henry Ford
Although Henry Ford's name is closely associated with the concept of mass
production, he should receive equal credit for introducing labor practices as early as
1913 that would be considered advanced even by today's standards. Safety measures
were improved, and the work day was reduced to eight hours, compared with the ten-or
twelve-hour day common at the time. In order to accommodate the shorter work day, the
entire factory was converted from two to three shifts.
In addition, sick leaves as well as improved medical care for those injured on the job
were instituted. The Ford Motor Company was one of the first factories to develop a
technical school to train specialized skilled laborers and an English language school for
immigrants. Some efforts were even made to hire the handicapped and provide jobs for
former convicts.
The most widely acclaimed innovation was the five-dollar-a-day minimum wage
that was offered in order to recruit and retain the best mechanics and to discourage the
growth of labor unions. Ford explained the new wage policy in terms of efficiency and
profit sharing. He also mentioned the fact that his employees would be able to purchase
the automobiles that they produced -- in effect creating a market for the product. In order
to qualify for the minimum wage, an employee had to establish a decent home and
demonstrate good personal habits, including sobriety, thriftiness, industriousness, and
dependability. Although some criticism was directed at Ford for involving himself too
much in the personal lives of his employees, there can be no doubt that, at a time when
immigrants were being taken advantage of in frightful ways, Henry Ford was helping
many people to establish themselves in America.
>24 Piano
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The ancestry of the piano can be traced to the early keyboard instruments of the
fifteenth and sixteenth centuries -- the spinet, the dulcimer, and the virginal. In the
seventeenth century the organ, the clavichord, and the harpsichord became the chief
instruments of the keyboard group, a supremacy they maintained until the piano
supplanted them at the end of the eighteenth century. The clavichord's tone was metallic
and never powerful; nevertheless, because of the variety of tone possible to it, many
composers found the clavichord a sympathetic instrument for intimate chamber music.
The harpsichord with its bright, vigorous tone was the favorite instrument for supporting
the bass of the small orchestra of the period and for concert use, but the character of the
tone could not be varied save by mechanical or structural devices.
The piano was perfected in the early eighteenth century by a harpsichord maker in
Italy(though musicologists point out several previous instances of the instrument). This
instrument was called a piano e forte (soft and loud), to indicate its dynamic versatility;
its strings were struck by a recoiling hammer with a felt-padded head. The wires were
much heavier in the earlier instruments. A series of mechanical improvements
continuing well into the nineteenth century, including the introduction of pedals to
sustain tone or to soften it, the perfection of a metal frame, and steel wire of the finest
quality, finally produced an instrument capable of myriad tonal effects from the most
delicate harmonies to an almost orchestral fullness of sound, from a liquid, singing tone
to a sharp, percussive brilliance.
>25 Movie Music
Accustomed though we are to speaking of the films made before 1927 as "silent", the
film has never been, in the full sense of the word, silent. From the very beginning, music
was regarded as an indispensable accompaniment; when the Lumiere films were shown
at the first public film exhibition in the United States in February 1896, they were
accompanied by piano improvisations on popular tunes. At first, the music played bore
no special relationship to the films; an accompaniment of any kind was sufficient.
Within a very short time, however, the incongruity of playing lively music to a solemn
film became apparent, and film pianists began to take some care in matching their pieces
to the mood of the film.
As movie theaters grew in number and importance, a violinist, and perhaps a cellist
would be added to the pianist in certain cases, and in the larger movie theaters small
orchestras were formed. For a number of years the selection of music for each film
program rested entirely in the hands of the conductor or leader of the orchestra, and very
often the principal qualification for holding such a position was not skill or taste so
much as the ownership of a large personal library of musical pieces. Since the conductor
seldom saw the films until the night before they were to be shown (if indeed, the
conductor was lucky enough to see them then), the musical arrangement was normally
improvised in the greatest hurry.
To help meet this difficulty, film distributing companies started the practice of
publishing suggestions for musical accompaniments. In 1909, for example, the Edison
Company began issuing with their films such indications of mood as "pleasant", "sad",
"lively". The suggestions became more explicit, and so emerged the musical cue sheet
containing indications of mood, the titles of suitable pieces of music, and precise
directions to show where one piece led into the next.
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Certain films had music especially composed for them. The most famous of these
early special scores was that composed and arranged for D. W. Griffith's film Birth of a
Nation, which was released in 1915.
>26 International Business andCross-cultural Communication
The increase in international business and in foreign investment has created a need
for executives with knowledge of foreign languages and skills in cross-cultural
communication. Americans, however, have not been well trained in either area and,
consequently, have not enjoyed the same level of success in negotiation in an
international arena as have their foreign counterparts.
Negotiating is the process of communicating back and forth for the purpose of
reaching an agreement. It involves persuasion and compromise, but in order to
participate in either one, the negotiators must understand the ways in which people are
persuaded and how compromise is reached within the culture of the negotiation.
In many international business negotiations abroad, Americans are perceived as
wealthy and impersonal. It often appears to the foreign negotiator that the American
represents a large multi-million-dollar corporation that can afford to pay the price
without bargaining further. The American negotiator's role becomes that of an
impersonal purveyor of information and cash.
In studies of American negotiators abroad, several traits have been identified that may
serve to confirm this stereotypical perception, while undermining the negotiator's
position. Two traits in particular that cause cross-cultural misunderstanding are
directness and impatience on the part of the American negotiator. Furthermore,
American negotiators often insist on realizing short-term goals. Foreign negotiators, on
the other hand, may value the relationship established between negotiators and may be
willing to invest time in it for long-term benefits. In order to solidify the relationship,
they may opt for indirect interactions without regard for the time involved in getting to
know the other negotiator.
Clearly, perceptions and differences in values affect the outcomes of negotiations
and the success of negotiators. For Americans to play a more effective role in
international business negotiations, they must put forth more effort to improve
cross-cultural understanding.
>27 Scientific Theories
In science, a theory is a reasonable explanation of observed events that are related. A
theory often involves an imaginary model that helps scientists picture the way an
observed event could be produced. A good example of this is found in the kinetic
molecular theory, in which gases are pictured as being made up of many small particles
that are in constant motion.
A useful theory, in addition to explaining past observations, helps to predict events
that have not as yet been observed. After a theory has been publicized, scientists design
experiments to test the theory. If observations confirm the scientists' predictions, the
theory is supported. If observations do not confirm the predictions, the scientists must
search further. There may be a fault in the experiment, or the theory may have to be
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revised or rejected.
Science involves imagination and creative thinking as well as collecting information
and performing experiments. Facts by themselves are not science. As the mathematician
Jules Henri Poincare said, "Science is built with facts just as a house is built with bricks,
but a collection of facts cannot be called science any more than a pile of bricks can be
called a house." Most scientists start an investigation by finding out what other scientists
have learned about a particular problem. After known facts have been gathered, the
scientist comes to the part of the investigation that requires considerable imagination.
Possible solutions to the problem are formulated. These possible solutions are called
hypotheses.
In a way, any hypothesis is a leap into the unknown. It extends the scientist's
thinking beyond the known facts. The scientist plans experiments, performs calculations,
and makes observations to test hypotheses. Without hypothesis, further investigation
lacks purpose and direction. When hypotheses are confirmed, they are incorporated into
theories.
>28 Changing Roles of Public Education
One of the most important social developments that helped to make possible a shift
in thinking about the role of public education was the effect of the baby boom of the
1950's and 1960's on the schools. In the 1920's, but especially in the Depression
conditions of the 1930's, the United States experienced a declining birth rate -- every
thousand women aged fifteen to forty-four gave birth to about 118 live children in
1 9 2 0 8 9 . 2 in 19 3 0 7 5 .8 in 1936, and 80 in 1940. With the growing prosperity brought
on by the Second World War and the economic boom that followed it young people
married and established households earlier and began to raise larger families than had
their predecessors during the Depression. Birth rates rose to 102 per thousand in 1946,
106.2 in 1950, and 118 in 1955. Although economics was probably the most important
determinant, it is not the only explanation for the baby boom. The increased value
placed on the idea of the family also helps to explain this rise in birth rates. The baby
boomers began streaming into the first grade by the mid 1940's and became a flood by
1950. The public school system suddenly found itself overtaxed. While the number of
schoolchildren rose because of wartime and postwar conditions, these same conditions
made the schools even less prepared to cope with the flood. The wartime economy
meant that few new schools were built between 1940 and 1945. Moreover, during the
war and in the boom times that followed, large numbers of teachers left their
profession for better-paying jobs elsewhere in the economy.
Therefore in the 1950's and 1960's, the baby boom hit an antiquated and inadequate
school system. Consequently, the "custodial rhetoric "of the 1930's and early 1940's no
longer made sense that is, keeping youths aged sixteen and older out of the labor
market by keeping them in school could no longer be a high priority for an institution
unable to find space and staff to teach younger children aged five to sixteen. With the
baby boom, the focus of educators and of laymen interested in education inevitably
turned toward the lower grades and back to basic academic skills and discipline. The
system no longer had much interest in offering nontraditional, new, and extra services
to older youths.
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>29 Telecommuting
Telecommuting -- substituting the computer for the trip to the job -- has been
hailed as a solution to all kinds of problems related to office work.
For workers it promises freedom from the office, less time wasted in traffic, and
help with child-care conflicts. For management, telecommuting helps keep high
performers on board, minimizes tardiness and absenteeism by eliminating commutes,
allows periods of solitude for high-concentration tasks, and provides scheduling
flexibility.
In some areas, such as Southern California and Seattle, Washington, local
governments are encouraging companies to start telecommuting programs in order to
reduce rush-hour congestion and improve air quality.
But these benefits do not come easily. Making a telecommuting program work
requires careful planning and an understanding of the differences between
telecommuting realities and popular images.
Many workers are seduced by rosy illusions of life as a telecommuter. A computer
programmer from New York City moves to the tranquil Adirondack Mountains and
stays in contact with her office via computer. A manager comes in to his office three
days a week and works at home the other two. An accountant stays home to care for her
sick child; she hooks up her telephone modem connections and does office work
between calls to the doctor.
These are powerful images, but they are a limited reflection of reality.
Telecommuting workers soon learn that it is almost impossible to concentrate on work
and care for a young child
at the same time. Before a certain age, young children cannot recognize, much less
respect, the necessary boundaries between work and family. Additional child support is
necessary if the parent is to get any work done.
Management too must separate the myth from the reality. Although the media has
paid a great deal of attention to telecommuting in most cases it is the employee's
situation, not the availability of technology that precipitates a telecommuting
arrangement.
That is partly why, despite the widespread press coverage, the number of companies
with work-at-home programs or policy guidelines remains small.
>30 The Origin of Refrigerators
By the mid-nineteenth century, the term "icebox" had entered the American
language, but ice was still only beginning to affect the diet of ordinary citizens in the
United States. The ice trade grew with the growth of cities. Ice was used in hotels,
taverns, and hospitals, and by some forward-looking city dealers in fresh meat, fresh fish,
and butter. After the Civil War (1861-1865), as ice was used to refrigerate freight cars, it
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also came into household use. Even before 1880, half the ice sold in New York,
Philadelphia, and Baltimore, and one-third of that sold in Boston and Chicago, went to
families for their own use. This had become possible because a new household
convenience, the icebox, a precursor of the modern refrigerator, had been invented.
Making an efficient icebox was not as easy as we might now suppose. In the early
nineteenth century, the knowledge of the physics of heat, which was essential to a
science of refrigeration, was rudimentary. The commonsense notion that the best icebox
was one that prevented the ice from melting was of course mistaken, for it was the
melting of the ice that performed the cooling. Nevertheless, early efforts to economize
ice included wrapping the ice in blankets, which kept the ice from doing its job. Not until
near the end of the nineteenth century did inventors achieve the delicate balance of
insulation and circulation needed for an efficient icebox.
But as early as 1803, an ingenious Maryland farmer, Thomas Moore, had been on the
right track. He owned a farm about twenty miles outside the city of Washington, for
which the village of Georgetown was the market center. When he used an icebox of his
own design to transport his butter to market, he found that customers would pass up the
rapidly melting stuff in the tubs of his competitors to pay a premium price for his butter,
still fresh and hard in neat, one-pound bricks. One advantage of his icebox, more
explained, was that farmers would no longer have to travel to market at night in order to
keep their produce cool.
>31 British Columbia
British Columbia is the third largest Canadian province, both in area and population.
It is nearly 1.5 times as large as Texas, and extends 800 miles (1,280km) north from the
United States border. It includes Canada's entire west coast and the islands just off the
coast.
Most of British Columbia is mountainous, with long rugged ranges running north
and south. Even the coastal islands are the remains of a mountain range that existed
thousands of years ago. During the last Ice Age, this range was scoured by glaciers until
most of it was beneath the sea. Its peaks now show as islands scattered along the coast.
The southwestern coastal region has a humid mild marine climate. Sea winds that
blow inland from the west are warmed by a current of warm water that flows through the
Pacific Ocean. As a result, winter temperatures average above freezing and summers are
mild. These warm western winds also carry moisture from the ocean.
Inland from the coast, the winds from the Pacific meet the mountain barriers of the
coastal ranges and the Rocky Mountains. As they rise to cross the mountains, the winds
are cooled, and their moisture begins to fall as rain. On some of the western slopes
almost 200 inches (500cm) of rain fall each year.
More than half of British Columbia is heavily forested. On mountain slopes that
receive plentiful rainfall, huge Douglas firs rise in towering columns. These forest
giants often grow to be as much as 300 feet (90m) tall, with diameters up to 10 feet
(3m). More lumber is produced from these trees than from any other kind of tree in
North America. Hemlock, red cedar, and balsam fir are among the other trees found in
British Columbia.
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>32 Botany
Botany, the study of plants, occupies a peculiar position in the history of human
knowledge. For many thousands of years it was the one field of awareness about which
humans had anything more than the vaguest of insights. It is impossible to know today
just what our Stone Age ancestors knew about plants, but from what we can observe of
preindustrial societies that still exist a detailed learning of plants and their properties
must be extremely ancient. This is logical. Plants are the basis of the food pyramid for
all living things even for other plants. They have always been enormously important to
the welfare of people not only for food, but also for clothing, weapons, tools, dyes,
medicines, shelter, and a great many other purposes. Tribes living today in the jungles
of the Amazon recognize literally hundreds of plants and know many properties of
each. To them, botany, as such, has no name and is probably not even recognized as a
special branch of "knowledge" at all.
Unfortunately, the more industrialized we become the farther away we move from
direct contact with plants, and the less distinct our knowledge of botany grows. Yet
everyone comes unconsciously on an amazing amount of botanical knowledge, and
few people will fail to recognize a rose, an apple, or an orchid. When our Neolithic
ancestors, living in the Middle East about 10, 000 years ago, discovered that certain
grasses could be harvested and their seeds planted for richer yields the next season the
first great step in a new association of plants and humans was taken. Grains were
discovered and from them flowed the marvel of agriculture: cultivated crops. From
then on, humans would increasingly take their living from the controlled production of
a few plants, rather than getting a little here and a little there from many varieties that
grew wild - and the accumulated knowledge of tens of thousands of years of
experience and intimacy with plants in the wild would begin to fade away.
>33 Plankton
Scattered through the seas of the world are billions of tons of small plants and
animals called plankton. Most of these plants and animals are too small for the human
eye to see. They drift about lazily with the currents, providing a basic food for many
larger animals.
Plankton has been described as the equivalent of the grasses that grow on the dry
land continents, and the comparison is an appropriate one. In potential food value,
however, plankton far outweighs that of the land grasses. One scientist has estimated
that while grasses of the world produce about 49 billion tons of valuable carbohydrates
each year, the sea's plankton generates more than twice as much.
Despite its enormous food potential, little effect was made until recently to farm
plankton as we farm grasses on land. Now marine scientists have at last begun to study
this possibility, especially as the sea's resources loom even more important as a means of
feeding an expanding world population.
No one yet has seriously suggested that "plankton burgers" may soon become
popular around the world. As a possible farmed supplementary food source, however,
20
plankton is gaining considerable interest among marine scientists.
One type of plankton that seems to have great harvest possibilities is a tiny
shrimplike creature called krill. Growing to two or three inches long, krill provide the
major food for the great blue whale, the largest animal ever inhabit the Earth. Realizing
that this whale may grow to 100 feet and weigh 150 tons at maturity, it is not surprising
that each one devours more than one ton of krill daily.
>34 Raising Oysters
In the past oysters were raised in much the same way as dirt farmers raised tomatoes
- by transplanting them. First, farmers selected the oyster bed, cleared the bottom of old
shells and other debris, then scattered clean shells about. Next, they "planted" fertilized
oyster eggs, which within two or three weeks hatched into larvae. The larvae drifted
until they attached themselves to the clean shells on the bottom. There they remained
and in time grew into baby oysters called seed or spat. The spat grew larger by drawing
in seawater from which they derived microscopic particles of food. Before long, farmers
gathered the baby oysters, transplanted them in other waters to speed up their growth,
then transplanted them once more into another body of water to fatten them up.
Until recently the supply of wild oysters and those crudely farmed were more than
enough to satisfy people's needs.
But today the delectable seafood is no longer available in abundance. The problem
has become so serious that some oyster beds have vanished entirely.
Fortunately, as far back as the early 1900's marine biologists realized that if new
measures were not taken, oysters would become extinct or at best a luxury food. So they
set up well-equipped hatcheries and went to work. But they did not have the proper
equipment or the skill to handle the eggs. They did not know when, what, and how to
feed the larvae. And they knew little about the predators that attack and eat baby oysters
by the millions. They failed, but they doggedly kept at it. Finally, in the 1940's a
significant breakthrough was made.
The marine biologists discovered that by raising the temperature of the water, they
could induce oysters to spawn not only in the summer but also in the fall, winter, and
spring. Later they developed a technique for feeding the larvae and rearing them to spat.
Going still further, they succeeded in breeding new strains that were resistant to diseases,
grew faster and larger, and flourished in water of different salinities and temperatures. In
addition, the cultivated oysters tasted better!
>35 Oil Refining
An important new industry, oil refining, grew after the Civil War. Crude oil, or
petroleum -- a dark, thick ooze from the earth -- had been known for hundreds of years,
but little use had ever been made of it. In the 1850's Samuel M. Kier, a manufacturer in
western Pennsylvania, began collecting the oil from local seepages and refining it into
kerosene. Refining, like smelting, is a process of removing impurities from a raw
material.
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Kerosene was used to light lamps. It was a cheap substitute for whale oil, which
was becoming harder to get. Soon there was a large demand for kerosene. People began
to search for new supplies of petroleum.
The first oil well was drilled by E. L. Drake, a retired railroad conductor. In 1859
he began drilling in Titusville, Pennsylvania. The whole venture seemed so
impractical and foolish that onlookers called it "Drake's Folly". But when he had
drilled down about 70 feet (21 meters), Drake struck oil. His well began to yield 20
barrels of crude oil a day.
News of Drake's success brought oil prospectors to the scene. By the early 1860's
these wildcatters were drilling for "black gold" all over western Pennsylvania. The
boom rivaled the California gold rush of 1848 in its excitement and Wild West
atmosphere. And it brought far more wealth to the prospectors than any gold rush.
Crude oil could be refined into many products. For some years kerosene continued to
be the principal one. It was sold in grocery stores and door-to-door. In the 1880's
refiners learned how to make other petroleum products such as waxes and lubricating
oils. Petroleum was not then used to make gasoline or heating oil.
>36 Plate Tectonics and Sea-floor Spreading
The theory of plate tectonics describes the motions of the lithosphere, the
comparatively rigid outer layer of the Earth that includes all the crust and part of the
underlying mantle. The lithosphere is divided into a few dozen plates of various
sizes and shapes; in general the plates are in motion with respect to one another. A
mid-ocean ridge is a boundary between plates where new lithospheric material is
injected from below. As the plates diverge from a mid-ocean ridge they slide on a
more yielding layer at the base of the lithosphere.
Since the size of the Earth is essentially constant, new lithosphere can be created
at the mid-ocean ridges only if an equal amount of lithospheric material is consumed
elsewhere. The site of this destruction is another kind of plate boundary: a
subduction zone. There one plate dives under the edge of another and is
reincorporated into the mantle. Both kinds of plate boundary are associated with fault
systems, earthquakes and volcanism, but the kinds of geologic activity observed at
the two boundaries are quite different.
The idea of sea-floor spreading actually preceded the theory of plate tectonics. In
its original version, in the early 1960's, it described the creation and destruction of the
ocean floor, but it did not specify rigid lithospheric plates. The hypothesis was
substantiated soon afterward by the discovery that periodic reversals of the Earth's
magnetic field are recorded in the oceanic crust. As magma rises under the
mid-ocean ridge, ferromagnetic minerals in the magma become magnetized in the
direction of the geomagnetic field. When the magma cools and solidifies, the
direction and the polarity of the field are preserved in the magnetized volcanic rock.
Reversals of the field give rise to a series of magnetic stripes running parallel to the
axis of the rift. The oceanic crust thus serves as a magnetic tape recording of the
history of the geomagnetic field that can be dated independently; the width of the
stripes indicates the rate of the sea-floor spreading.
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>37 Icebergs
Icebergs are among nature's most spectacular creations, and yet most people have
never seen one. A vague air of mystery envelops them. They come into being --
somewhere -- in faraway, frigid waters, amid thunderous noise and splashing
turbulence, which in most case no one hears or sees. They exist only a short time and
then slowly waste away just as unnoticed.
Objects of sheerest beauty they have been called. Appearing in an endless variety
of shapes, they may be dazzlingly white, or they may be glassy blue, green or purple,
tinted faintly or in darker hues. They are graceful, stately, inspiring -- in calm, sunlight
seas.
But they are also called frightening and dangerous, and that they are -- in the night,
in the fog, and in storms. Even in clear weather one is wise to stay a safe distance away
from them. Most of their bulk is hidden below the water, so their underwater parts may
extend out far beyond the visible top. Also, they may roll over unexpectedly, churning
the waters around them.
Icebergs are parts of glaciers that break off, drift into the water, float about awhile,
and finally melt. Icebergs afloat today are made of snowflakes that have fallen over
long ages of time. They embody snows that drifted down hundreds, or many thousands,
or in some cases maybe a million years ago. The snows fell in polar regions and on
cold mountains, where they melted only a little or not at all, and so collected to great
depths over the years and centuries.
As each year's snow accumulation lay on the surface, evaporation and melting
caused the snowflakes slowly to lose their feathery points and become tiny grains of
ice. When new snow fell on top of the old, it too turned to icy grains. So blankets of
snow and ice grains mounted layer upon layer and were of such great thickness that the
weight of the upper layers compressed the lower ones. With time and pressure from
above, the many small ice grains joined and changed to larger crystals, and eventually
the deeper crystals merged into a solid mass of ice.
>38 Topaz
Topaz is a hard, transparent mineral. It is a compound of aluminum, silica, and
fluorine. Gem topaz is valuable. Jewelers call this variety of the stone "precious topaz".
The best-known precious topaz gems range in color from rich yellow to light brown or
pinkish red. Topaz is one of the hardest gem minerals. In the mineral table of hardness,
it has a rating of 8, which means that a knife cannot cut it, and that topaz will scratch
quartz.
The golden variety of precious topaz is quite uncommon. Most of the world's topaz
is white or blue. The white and blue crystals of topaz are large, often weighing
thousands of carats. For this reason, the value of topaz does not depend so much on its
size as it does with diamonds and many other precious stones, where the value
increases about four times with each doubling of weight. The value of a topaz is
largely determined by its quality. But color is also important: blue topaz, for instance,
23
is often irradiated to deepen and improve its color.
Blue topaz is often sold as aquamarine and a variety of brown quartz is widely sold
as topaz. The quartz is much less brilliant and more plentiful than true topaz. Most of
it is a variety of amethyst: that heat has turned brown.
>39 The Salinity of Ocean Waters
If the salinity of ocean waters is analyzed, it is found to vary only slightly from place
to place. Nevertheless, some of these small changes are important. There are three
basic processes that cause a change in oceanic salinity.
One of these is the subtraction of water from the ocean by means of evaporation -
conversion of liquid water to water vapor. In this manner the salinity is increased,
since the salts stay behind. If this is carried to the extreme, of course, white crystals of
salt would be left behind.
The opposite of evaporation is precipitation, such as rain, by which water is added
to the ocean. Here the ocean is being diluted so that the salinity is decreased. This may
occur in areas of high rainfall or in coastal regions where rivers flow into the ocean.
Thus salinity may be increased by the subtraction of water by evaporation, or
decreased by the addition of fresh water by precipitation or runoff.
Normally, in tropical regions where the sun is very strong, the ocean salinity is
somewhat higher than it is in other parts of the world where there is not as much
evaporation. Similarly, in coastal regions where rivers dilute the sea, salinity is
somewhat lower than in other oceanic areas.
A third process by which salinity may be altered is associated with the formation
and melting of sea ice. When sea water is frozen, the dissolved materials are left
behind. In this manner, sea water directly beneath freshly formed sea ice has a higher
salinity than it did before the ice appeared. Of course, when this ice melts, it will tend
to decrease the salinity of the surrounding water. In the Weddell Sea Antarctica, the
densest water in the oceans is formed as a result of this freezing process, which
increases the salinity of cold water. This heavy water sinks and is found in the deeper
portions of the oceans of the world.
>40 Cohesion-tension Theory
Atmospheric pressure can support a column of water up to 10 meters high. But plants
can move water much higher; the sequoia tree can pump water to its very top more
than 100 meters above the ground. Until the end of the nineteenth century, the
movement of water in trees and other tall plants was a mystery. Some botanists
hypothesized that the living cells of plants acted as pumps. But many experiments
demonstrated that the stems of plants in which all the cells are killed can still move
water to appreciable heights. Other explanations for the movement of water in plants
have been based on root pressure, a push on the water from the roots at the bottom of
the plant. But root pressure is not nearly great enough to push water to the tops of tall
trees. Furthermore, the conifers, which are among the tallest trees, have unusually low
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root pressures.
If water is not pumped to the top of a tall tree, and if it is not pushed to the top of a
tall tree, then we may ask: how does it get there? According to the currently accepted
cohesion-tension theory, water is pulled there. The pull on a rising column of water in
a plant results from the evaporation of water at the top of the plant. As water is lost
from the surface of the leaves, a negative pressure, or tension, is created. The
evaporated water is replaced by water moving from inside the plant in unbroken
columns that extend from the top of a plant to its roots. The same forces that create
surface tension in any sample of water are responsible for the maintenance of these
unbroken columns of water. When water is confined in tubes of very small bore, the
forces of cohesion (the attraction between water molecules) are so great that the
strength of a column of water compares with the strength of a steel wire of the same
diameter. This cohesive strength permits columns of water to be pulled to great
heights without being broken.
>41 American Black Bears
American black bears appear in a variety of colors despite their name. In the
eastern part of their range, most of these bears have shiny black fur, but in the west
they grow brown, red, or even yellow coats. To the north, the black bear is actually
gray or white in color. Even in the same litter, both brown and black furred bears may
be born.
Black bears are the smallest of all American bears, ranging in length from five to
six feet, weighing from three hundred to five hundred pounds. Their eyes and ears are
small and their eyesight and hearing are not as good as their sense of smell.
Like all bears, the black bear is timid, clumsy, and rarely dangerous, but if
attacked, most can climb trees and cover ground at great speeds. When angry or
frightened, it is a formidable enemy.
Black bears feed on leaves, herbs, roots, fruit, berries, insects, fish, and even larger
animals. One of the most interesting characteristics of bears, including the black bear,
is their winter sleep. Unlike squirrels, woodchucks, and many other woodland animals,
bears do not actually hibernate. Although the bear does not eat during the winter
months, sustaining itself from body fat, its temperature remains almost normal, and it
breathes regularly four or five times per minute.
Most black bears live alone, except during mating season. They prefer to live in
caves, hollow logs, or dense thickets. A litter of one to four cubs is born in January or
February after a gestation period of six to nine months, and they remain with their
mother until they are fully grown or about one and a half years old. Black bears can
live as long as thirty years in the wild, and even longer in game preserves set aside for
them.
>42 Coal-fired Power Plants
The invention of the incandescent light bulb by Thomas A. Edison in 1879 created
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a demand for a cheap, readily available fuel with which to generate large amounts of
electric power. Coal seemed to fit the bill, and it fueled the earliest power stations
(which were set up at the end of the nineteenth century by Edison himself). As more
power plants were constructed throughout the country, the reliance on coal increased.
Since the First World War, coal-fired power plants have accounted for about half of
the electricity produced in the United States each year. In 1986 such plants had a
combined generating capacity of 289, 000 megawatts and consumed 83 percent of the
nearly 900 million tons of coal mined in the country that year. Given the uncertainty in
the future growth of nuclear power and in the supply of oil and natural gas, coal-fired
power plants could well provide up to 70 percent of the electric power in the United
States by the end of the century.
Yet, in spite of the fact that coal has long been a source of electricity and may remain
one for many years (coal represents about 80 percent of United States fossil-fuel
reserves), it has actually never been the most desirable fossil fuel for power plants. Coal
contains less energy per unit of weight than natural gas or oil; it is difficult to transport,
and it is associated with a host of environmental issues, among them acid rain. Since the
late 1960's problems of emission control and waste disposal have sharply reduced the
appeal of coal-fired power plants. The cost of ameliorating these environmental
problems along with the rising cost of building a facility as large and complex as a
coal-fired power plant, have also made such plants less attractive from a purely
economic perspective.
Changes in the technological base of coal-fired power plants could restore their
attractiveness, however. Whereas some of these changes are evolutionary and are intended
mainly to increase the productivity of existing plants, completely new technologies for
burning coal cleanly are also being developed.
>43 Statistics
There were two widely divergent influences on the early development of statistical
methods. Statistics had a mother who was dedicated to keeping orderly records of
governmental units (state and statistics come from the same Latin root status) and a
gentlemanly gambling father who relied on mathematics to increase his skill at playing the
odds in games of chance. The influence of the mother on the offspring, statistics, is
represented by counting, measuring, describing, tabulating, ordering, and the taking of
censuses -- all of which led to modern descriptive statistics. From the influence of the
father came modern inferential statistics, which is based squarely on theories of
probability.
Descriptive statistics involves tabulating, depicting and describing collections of data.
These data may be quantitative such as measures of height, intelligence or grade level --
variables that are characterized by an underlying continuum -- or the data may represent
qualitative variables, such as sex, college major or personality type. Large masses of data
must generally undergo a process of summarization or reduction before they are
comprehensible. Descriptive statistics is a tool for describing or summarizing or reducing
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to comprehensible form the properties of an otherwise unwieldy mass of data.
Inferential statistics is a formalized body of methods for solving another class of
problems that present great difficulties for the unaided human mind. This general class
of problems characteristically involves attempts to make predictions using a sample of
observations. For example, a school superintendent wishes to determine the proportion
of children in a large school system that come to school without breakfast, have been
vaccinated for flu, or whatever. Having a little knowledge of statistics, the
superintendent would know that it is unnecessary and inefficient to question each child:
the proportion for the entire district could be estimated fairly accurately from a sample
of as few as 100 children. Thus, the purpose of inferential statistics is to predict or
estimate characteristics of a population from a knowledge of the characteristics of only
a sample of the population.
>44 Obtaining Fresh Water from Icebergs
The concept of obtaining fresh water from icebergs that are towed to populated areas
and arid regions of the world was once treated as a joke more appropriate to cartoons
than real life. But now it is being considered quite seriously by many nations,
especially since scientists have warned that the human race will outgrow its fresh
water supply faster than it runs out of food.
Glaciers are a possible source of fresh water that has been overlooked until
recently. Three-quarters of the Earth's fresh water supply is still tied up in glacial ice,
a reservoir of untapped fresh water so immense that it could sustain all the rivers of the
world for 1,000 years. Floating on the oceans every year are 7,659 trillion metric tons
of ice encased in 10,000 icebergs that break away from the polar ice caps, more than
ninety percent of them from Antarctica.
Huge glaciers that stretch over the shallow continental shelf give birth to icebergs
throughout the year. Icebergs are not like sea ice, which is formed when the sea itself
freezes, rather, they are formed entirely on land, breaking off when glaciers spread
over the sea. As they drift away from the polar region, icebergs sometimes move
mysteriously in a direction opposite to the wind, pulled by subsurface currents. Because
they melt more slowly than smaller pieces of ice, icebergs have been known to drift as
far north as 35 degrees south of the equator in the Atlantic Ocean. To corral them and
steer them to parts of the world where they are needed would not be too difficult.
The difficulty arises in other technical matters, such as the prevention of rapid
melting in warmer climates and the funneling of fresh water to shore in great volume.
But even if the icebergs lost half of their volume in towing, the water they could provide
would be far cheaper than that produced by desalinization, or removing salt from water.
>45 The Source of Energy
A summary of the physical and chemical nature of life must begin, not on the Earth,
but in the Sun; in fact, at the Sun's very center. It is here that is to be found the source of
the energy that the Sun constantly pours out into space as light and heat. This energy is
liberated at the center of the Sun as billions upon billions of nuclei of hydrogen atoms
27
collide with each other and fuse together to form nuclei of helium, and in doing so, release
some of the energy that is stored in the nuclei of atoms. The output of light and heat of the
Sun requires that some 600 million tons of hydrogen be converted into helium in the Sun
every second. This the Sun has been doing for several thousands of millions of years.
The nuclear energy is released at the Sun's center as high-energy gamma radiation, a
form of electromagnetic radiation like light and radio waves, only of very much shorter
wavelength. This gamma radiation is absorbed by atoms inside the Sun to be reemitted at
slightly longer wavelengths. This radiation, in its turn is absorbed and reemitted. As the
energy filters through the layers of the solar interior, it passes through the X-ray part of
the spectrum eventually becoming light. At this stage, it has reached what we call the
solar surface, and can escape into space without being absorbed further by solar atoms.
A very small fraction of the Sun's light and heat is emitted in such directions that after
passing unhindered through interplanetary space, it hits the Earth.
>46 Vision
Human vision like that of other primates has evolved in an arboreal environment. In the
dense complex world of a tropical forest, it is more important to see well than to develop an
acute sense of smell. In the course of evolution members of the primate line have acquired
large eyes while the snout has shrunk to give the eye an unimpeded view. Of mammals only
humans and some primates enjoy color vision. The red flag is black to the bull. Horses live
in a monochrome world. Light visible to human eyes however occupies only a very narrow
band in the whole electromagnetic spectrum. Ultraviolet rays are invisible to humans
though ants and honeybees are sensitive to them. Humans have no direct perception of
infrared rays unlike the rattlesnake which has receptors tuned into wavelengths longer than
0.7 micron. The world would look eerily different if human eyes were sensitive to infrared
radiation. Then instead of the darkness of night, we would be able to move easily in a
strange shadowless world where objects glowed with varying degrees of intensity. But
human eyes excel in other ways. They are in fact remarkably discerning in color gradation.
The color sensitivity of normal human vision is rarely surpassed even by sophisticated
technical devices.
>47 Folk Cultures
A folk culture is a small isolated, cohesive, conservative, nearly self-sufficient group
that is homogeneous in custom and race with a strong family or clan structure and highly
developed rituals. Order is maintained through sanctions based in the religion or family
and interpersonal relationships are strong. Tradition is paramount, and change comes
infrequently and slowly. There is relatively little division of labor into specialized duties.
Rather, each person is expected to perform a great variety of tasks, though duties may differ
between the sexes. Most goods are handmade and subsistence economy prevails.
Individualism is weakly developed in folk cultures as are social classes. Unaltered folk
cultures no longer exist in industrialized countries such as the United States and Canada.
Perhaps the nearest modern equivalent in Anglo America is the Amish, a German
American farming sect that largely renounces the products and labor saving devices of the
industrial age. In Amish areas, horse drawn buggies still serve as a local transportation
device and the faithful are not permitted to own automobiles. The Amish's central religious
concept of Demut "humility", clearly reflects the weakness of individualism and social
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class so typical of folk cultures and there is a corresponding strength of Amish group
identity. Rarely do the Amish marry outside their sect. The religion, a variety of the
Mennonite faith, provides the principal mechanism for maintaining orders.
By contrast a popular culture is a large heterogeneous group often highly
individualistic and constantly changing. Relationships tend to be impersonal and a
pronounced division of labor exists, leading to the establishment of many specialized
professions. Secular institutions of control such as the police and army take the place of
religion and family in maintaining order, and a money-based economy prevails. Because of
these contrasts, "popular" may be viewed as clearly different from "folk". The popular is
replacing the folk in industrialized countries and in many developing nations. Folk-made
objects give way to their popular equivalent, usually because the popular item is more
quickly or cheaply produced, is easier or time saving to use or leads more prestige to the
owner.
>48 Bacteria
Bacteria are extremely small living things. While we measure our own sizes in inches
or centimeters, bacterial size is measured in microns. One micron is a thousandth of a
millimeter: a pinhead is about a millimeter across. Rod-shaped bacteria are usually from
two to four microns long, while rounded ones are generally one micron in diameter. Thus if
you enlarged a rounded bacterium a thousand times, it would be just about the size of a
pinhead. An adult human magnified by the same amount would be over a mile (1.6
kilometers) tall.
Even with an ordinary microscope, you must look closely to see bacteria. Using a
magnification of 100 times, one finds that bacteria are barely visible as tiny rods or dots.
One cannot make out anything of their structure. Using special stains, one can see that
some bacteria have attached to them wavy-looking "hairs" called flagella. Others have only
one flagellum. The flagella rotate, pushing the bacteria through the water. Many bacteria
lack flagella and cannot move about by their own power, while others can glide along over
surfaces by some little-understood mechanism.
From the bacterial point of view, the world is a very different place from what it is to
humans. To a bacterium water is as thick as molasses is to us. Bacteria are so small that
they are influenced by the movements of the chemical molecules around them. Bacteria
under the microscope, even those with no flagella, often bounce about in the water. This is
because they collide with the water molecules and are pushed this way and that. Molecules
move so rapidly that within a tenth of a second the molecules around a bacterium have all
been replaced by new ones; even bacteria without flagella are thus constantly exposed to a
changing environment.
>49 Sleep
Sleep is part of a person's daily activity cycle. There are several different stages of sleep,
and they too occur in cycles. If you are an average sleeper, your sleep cycle is as follows.
When you first drift off into slumber, your eyes will roll about a bit, your temperature will
drop slightly, your muscles will relax, and your breathing well slow and become quite
29
regular. Your brain waves slow down a bit too, with the alpha rhythm of rather fast waves
predominating for the first few minutes. This is called stage 1 sleep. For the next half hour or
so, as you relax more and more, you will drift down through stage 2 and stage 3 sleep. The
lower your stage of sleep, the slower your brain waves will be. Then about 40 to 60 minutes
after you lose consciousness you will have reached the deepest sleep of all. Your brain waves
will show the large slow waves that are known as the delta rhythm. This is stage 4 sleep.
You do not remain at this deep fourth stage all night long, but instead about 80 minutes
after you fall into slumber, your brain activity level will increase again slightly. The delta
rhythm will disappear, to be replaced by the activity pattern of brain waves. Your eyes will
begin to dart around under your closed eyelids as if you were looking at something occurring
in front of you. This period of rapid eye movement lasts for some 8 to 15 minutes and is
called REM sleep. It is during REM sleep period, your body will soon relax again, your
breathing will grow slow and regular once more, and you will slip gently back from stage 1
to stage 4 sleep - only to rise once again to the surface of near consciousness some 80
minutes later.
>50 Cells and Temperature
Cells cannot remain alive outside certain limits of temperature, and much narrower limits
mark the boundaries of effective functioning. Enzyme systems of mammals and birds are
most ; efficient only within a narrow range around 37 a departure of a few degrees from this
value seriously impairs their functioning. Even though cells can survive wider fluctuations,
the integrated actions of bodily systems are impaired. Other animals have a wider tolerance
for changes of bodily temperature. For centuries it has been recognized that mammals and
birds differ from other animals in the way they regulate body temperature. Ways of
characterizing the difference have become more accurate and meaningful over time, but
popular terminology still reflects the old division into "warm blooded" and "cold blooded"
species; warm-blooded included mammals and birds whereas all other creatures were
considered cold-blooded. As more species were studied, it became evident that this
classification was inadequate. A fence lizard or a desert iguana -- each cold-blooded --
usually has a body temperature only a degree or two below that of humans and so is not
cold. Therefore the next distinction was made between animals that maintain a constant
body temperature, called homeotherms, and those whose body temperature varies with
their environment, called poikilotherms. But this classification also proved inadequate,
because among mammals there are many that vary their body temperatures during
hibernation. Furthermore, many invertebrates that live in the depths of the ocean never
experience a change in the chill of the deep water, and their body temperatures remain
constant.
> 5 1 M a r i n e M a m m a l s
Since there is such an abundance of food in the sea, it is understandable that some of the
efficient, highly adaptable, warm-blooded mammals that evolved on land should have
returned to the sea. Those that did have flourished. Within about 50 million years -- no time
at all, geologically speaking -- one of the four kinds of mammals that has returned to a
marine environment has developed into the largest of all animal forms, the whale. A
second kind, the seal, has produced what is probably the greatest population of large
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carnivorous mammals on Earth.
This suggests that these "top dogs" of the ocean are prospering and multiplying.
However, such has not been the case, at least not for the last 150 years. Trouble has closed
in on these mammals in the form of equally warm-blooded and even more efficient and
adaptable predators, humans. At sea, as on land, humans have now positioned themselves
on the top of the whole great pyramid of life, and they have caused serious problems for the
mammals of the sea. There is a simple reason for this. Marine mammals have the
misfortune to be swimming aggregates of commodities that humans want: fur, oil and meat.
Even so, they might not be so vulnerable to human depredation if they did not, like humans,
reproduce so slowly. Every year humans take more than 50 million tons of fish from the
oceans without critically depleting the population of any species. But the slow-breeding
mammals of the sea have been all but wiped out by humans seeking to satisfy their wants
and whims.
> 52 Ch i mp a n z ee
The most striking single fact about chimpanzees is the flexibility of their social life, the
lack of any rigid form of organization. It represents about as far a departure from the
baboon type of organization as one can find among the higher primates, and serves to
emphasize the great variety of primate adaptations. Chimpanzees are more human than
baboons, or rather they jibe better with the way we like to picture ourselves, as
free-wheeling individuals who tend to be unpredictable, do not take readily to any form of
regimentation, and are frequently charming. (Charm is relatively rare among baboons.)
Two researchers have described what they found during more than eight months spent
among chimpanzees in their natural habitat the forest: "We were quite surprised to observe
that there is no single distinct social unit in chimpanzee society. Not only is there no
'family' or 'harem' organization; neither is there a 'troop' organization - that is to say, no
particular chimpanzees keep permanently together. On the contrary, individuals move
about at will, alone or in small groups best described as bands, which sometimes form into
large aggregations.
They leave their associates if they want to, and join up with new ones without conflict.
“The general practice is best described as "easy come, easy go”, although there are certain
group-forming tendencies. As a rule chimpanzees move about in one of four types of band:
adult males only; mothers and offspring and occasionally a few other females; adults and
adolescents of both sexes, but no mothers with young and representatives of all categories
mixed together. The composition of bands may change a number of times during the course
of a day as individuals wander off and groups split or combine with other groups. On the
other hand, certain individuals prefer one another's company. One of the researchers
observed that four males often roamed together over a four-month period, and mothers
often associated with their older offspring.
>53 Nitinol
Nitinol is one of the most extraordinary metals to be discovered this century: A simple
alloy of nickel and titanium, nitinol has some perplexing properties. A metal with a
memory, it can be made to remember any shape into which it is fashioned, returning to that
31
shape whenever it is heated.
For example, a piece of nitinol wire bent to form a circle that is then heated and
quenched will remember this shape. It may then be bent or crumpled, but on reheating, will
violently untwist, reforming its original shape. This remarkable ability is called Shape
Memory Effect (SME); other alloys, such as brasses, are known to possess it to a limited
extent. No one fully understands SME, and nitinol remains particularly perplexing, for,
whenever it performs this peculiar feat, it appears to be breaking the laws of
thermodynamics by springing back into shape with greater force than was used to deform it
in the first place.
But not only is nitinol capable of remembering, it also has the ability to "learn". If the
heating-cooling-crumpling-reheating process is carried out sufficiently often, and the
metal is always crumpled in exactly the same way, the nitinol will not only remember its
original shape, but gradually it learns to remember its crumpled form as well, and will
begin to return to the same crumpled shape every time it is cooled. Eventually, the metal
will crumple and uncrumple, totally unaided, in response to changes in temperature and
without any sign of metal fatigue.
Engineers have produced prototype engines that are driven by the force of nitinol
springing from one shape to another as it alternately encounters hot and cold water. The
energy from these remarkable engines is, however, not entirely free: heat energy is
required to produce the temperature differences needed to run the engine. But the optimum
temperatures at which the metal reacts can be controlled by altering the proportions of
nickel to titanium; some alloys will even perform at room temperature. The necessary
temperature range between the warm and the cold can be as little as twelve degrees
centigrade.
>54 Treasure in Sunken Ships
Of the tens of thousands of ships on the ocean bottom, only a handful, less than 1
percent, contain negotiable treasure, such as gold and jewels. Most give us a different
priceless treasure -- history. A sunken ship lies in trust, preserved in the airless
environment of the sea and those in deep water are especially well protected. No dry land
sites anywhere -- except perhaps Egyptian tombs -- are in a better state of preservation than
a vessel deep in the ocean. A sunken ship, therefore, can be a rare window through which a
moment in time is glimpsed.
This is not to imply that sunken ships are always found intact. Most ships break up on
the way down, hit the bottom at about 100 miles per hour, and become a chaotic, confusing
jumble. I recall the chagrin of a novice diver who, after surfacing from an underwater tour
of a 400-foot ship, asked his diving buddy, "Where was the wreck?" It takes experience to
actually know a sunken ship when one sees it. But no matter what its condition on the way
down, a ship deteriorates much more slowly as it sinks deeper into protective layers of sand
and mud. Ancient vessels have been found in remarkably good condition. In 1977 a group
of marine archaeologists excavating a 900-year-old wreck recovered engraved glassware.
Greek coins, bronze kettles, and amazingly, Greek jars containing seeds, almonds, and
lentils -- even a plate with chicken bones.
>55 Creating Colors
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There are two ways to create colors in a photograph. One method, called additive, starts
with three basic colors and adds them together to produce some other colors. The second
method, called subtractive, starts with white light (a mixture of all colors in the spectrum)
and by taking away some or all other colors leaves the one desired.
In the additive method separate colored lights are combined to produce various other
colors. The three additive primary colors are green, red and blue (each proportion, about
one third of the wavelengths in the total spectrum). Mixed in varying proportions, they can
produce all colors. Green and red light mix to produce yellow, red and blue light mix to
produce magenta, green and blue mix to produce cyan. When equal parts of all three of
these primary colored beams of light overlap, the mixture appears white to the eye.
In the subtractive process, colors are produced when dye (as in paint or color
photographic materials) absorbs some wavelengths and so passes on only part of the
spectrum. The subtractive primaries are cyan (a bluish green), magenta (a purplish pink),
and yellow; these are the pigments or dyes that absorb red, green and blue wavelengths,
respectively, thus subtracting them from white light. These dye colors are the
complementary colors to the three additive primaries of red, green and blue. Properly
combined, the subtractive primaries can absorb all colors of light, producing black. But,
mixed in varying proportions they too can produce any color in the spectrum.
Whether a particular color is obtained by adding colored lights together or by
subtracting some light from the total spectrum, the result looks the same to the eye. The
additive process was employed for early color photography. But the subtractive method,
while requiring complex chemical techniques, has turned out to be more practical and is
the basis of all modern color films.
>56 The Organic Foods
Are organically grown foods the best food choices? The advantages claimed for such
foods over conventionally grown and marketed food products are now being debated.
Advocates of organic foods -- a term whose meaning varies greatly -- frequently proclaim
that such products are safer and more nutritious than others.
The growing interest of consumers in the safety and nutritional quality of the typical
North American diet is a welcome development. However, much of this interest has been
sparked by sweeping claims that the food supply is unsafe or inadequate in meeting
nutritional needs. Although most of these claims are not supported by scientific evidence,
the preponderance of written material advancing such claims makes it difficult for the
general public to separate fact from fiction. As a result, claims that eating a diet consisting
entirely of organically grown foods prevents or cures disease or provides other benefits to
health have become widely publicized and form the basis for folklore.
Almost daily the public is besieged by claims for "no-aging" diets, new vitamins and
other wonder foods. There are numerous unsubstantiated reports that natural vitamins are
superior to synthetic ones, that fertilized eggs are nutritionally superior to unfertilized eggs,
that untreated grains are better than fumigated grains and the like.
One thing that most organically grown food products seem to have in common is that
they cost more than conventionally grown foods. But in many cases consumers are misled
if they believe organic foods can maintain health and provide better nutritional quality than
conventionally grown foods. So there is real cause for concern if consumers particularly
33
those with limited incomes, distrust the regular food supply and buy only expensive
organic foods instead.
>57 Lighthouses
The first navigational lights in the New World were probably lanterns hung at harbor
entrances. The first lighthouse was put up by the Massachusetts Bay Colony in 1716 on
Little Brewster Island at the entrance to Boston Harbor. Paid for and maintained by "light
dues" levied on ships, the original beacon was blown up in 1776. By then there were only a
dozen or so true lighthouses in the colonies. Little over a century later, there were 700
lighthouses.
The first light erected on the West Coast in the 1850's featured the same basic New
England design: a Cape Cod dwelling with the tower rising from the center or standing
close by. In New England and elsewhere, though, lighthouses reflected a variety of
architectural styles. Since most stations in the Northeast were built on rocky eminences,
enormous towers were not the rule. Some were made of stone and brick, others of wood or
metal. Some stood on pilings or stilts; some were fastened to rock with iron rods. Farther
south, from Maryland through the Florida Keys, the coast was low and sandy. It was often
necessary to build tall towers there - massive structures like the majestic Cape Hatteras,
North Carolina, lighthouse, which was lit in 1870. At 190 feet, it is the tallest brick
lighthouse in the country.
Notwithstanding differences in appearance and construction, most American
lighthouses shared several features: a light, living quarters and sometimes a bell (or later, a
foghorn).They also had something else in common: a keeper and, usually, the keeper's
family. The keeper's essential task was trimming the lantern wick in order to maintain a
steady, bright flame. The earliest keepers came from every walk of life - they were seamen,
farmers, mechanics, and rough mill hands - and appointments were often handed out by
local customs commissioners as political plums. After the administration of lighthouses
was taken over in 1852 by the United States Lighthouse Board, an agency of the Treasury
Department, the keeper corps gradually became highly professional.
>58 Animals' Compasses
Researchers have found that migrating animals use a variety of inner compasses to help
them navigate. Some steer by the position of the Sun. Others navigate by the stars. Some
use the Sun as their guide during the day and then switch to star navigation by night. One
study shows that the homing pigeon uses the Earth's magnetic fields as a guide in finding
its way home and there are indications that various other animals from insects to mollusks,
can also make use of magnetic compasses. It is of course very useful for a migrating bird to
be able to switch to a magnetic compass when clouds cover the Sun; otherwise it would just
have to land and wait for the Sun to come out again.
Even with the Sun or stars to steer by, the problems of navigation are more complicated
than they might seem at first. For example, a worker honeybee that has found a rich source
of nectar and pollen flies rapidly home to the hive to report. A naturalist has discovered
that the bee scout delivers her report through a complicated dance in the hive, in which she
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tells the other workers not only how far away the food is, but also what direction to fly in
relation to the Sun. But the Sun does not stay in one place all day. As the workers start out
to gather the food, the Sun may already have changed its position in the sky somewhat. In
later trips during the day, the Sun will seem to move farther and farther toward the west.
Yet the worker bees seem to have no trouble at all in finding the food source. Their inner
clocks tell them just where the Sun will be and they change their course correspondingly.
>59 Muscles and Human
Body It is in the joints of the human body that movements of the bones take place. The
movement itself is caused by the pull of sheets and cords of very tough tissue called muscle.
Muscle tissue has the special ability to shorten itself so that the bone on which it pulls has to
move. When muscle tissue shortens, it also bunches up. Muscle tissue covers the body in
sheets and bands that lie between the skin and the skeleton. The bones are the framework of
the body, but the muscles fill out the body shape. Most muscles extend from one bone to
another. When the muscle between the bones shortens, one bone has to move. The point
where the muscle is fastened to the unmoving bone is called the origin of the muscle,
whereas the point where the muscle is not fastened to the bone that is to be moved is called
the insertion. Sometimes the muscle is not attached directly to the bone but to a tough,
nonstretchable cord, or tendon, that is attached to the bone. Muscles do not push; they can
only pull. To bend the arm at the elbow, the muscle at the front of the upper arm has to
shorten and bunch up. To unbend the arm other muscles in the back of the arm have to
shorten. These two sets of muscles - the front and the back - are said to act in opposition to
each other. When one set is working, the other set is usually relaxed. But there are times
when both of them work. Sometimes muscles are called upon to do more than simply pull
in one direction. They may have to perform a turning motion. To be able to do this, the
muscle must be attached to the bone at an angle. By pulling, the muscle can cause the bone
to pivot. A few muscles have special functions. The diaphragm, for example, forces the
lungs to take in air. This part of breathing is not primarily a bone moving operation.
>60 Colds and Age
A critical factor that plays a part in susceptibility to colds is age. A study done by the
University of Michigan School of Public Health revealed particulars that seem to hold true
for the general population. Infants are the most cold ridden group, averaging more than six
colds in their first years. Boys have more colds than girls up to age three. After the age of
three, girls are more susceptible than boys, and teenage girls average three colds a year to
boys' two. The general incidence of colds continues to decline into maturity. Elderly
people who are in good health have as few as one or two colds annually. One exception is
found among people in their twenties, especially women, who show a rise in cold
infections, because people in this age group are most likely to have young children. Adults
who delay having children until their thirties and forties experience the same sudden
increase in cold infections. The study also found that economics plays an important role. As
income increases, the frequency at which colds are reported in the family decreases.
Families with the lowest income suffer about a third more colds than families at the upper
end. Lower income generally forces people to live in more cramped quarters than those
typically occupied by wealthier people, and crowding increases the opportunities for the
cold virus to travel from person to person. Low income may also adversely influence diet.
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The degree to which poor nutrition affects susceptibility to colds is not yet clearly
established, but an inadequate diet is suspected of lowering resistance generally.
>61 Pottery
Ancient people made clay pottery because they needed it for their survival. They used
the pots they made for cooking, storing food, and carrying things from place to place.
Pottery was so important to early cultures that scientists now study it to learn more about
ancient civilizations. The more advanced the pottery in terms of decoration, materials,
glazes and manufacture, the more advanced the culture itself.
The artisan who makes pottery in North America today utilizes his or her skill and
imagination to create items that are beautiful as well as functional, transforming something
ordinary into something special and unique.
The potter uses one of the Earth's most basic materials, clay. Clay can be found almost
anywhere. Good pottery clay must be free from all small stones and other hard materials
that would make the potting process difficult. Most North American artisan potters now
purchase commercially processed clay, but some find the clay they need right in the earth
close to where they work.
The most important tools potters use are their own hands; however, they also use wire
loop tools, wooden modeling tools, plain wire, and sponges. Plain wire is used to cut away
the finished pot from its base on the potter's wheel.
After a finished pot is dried of all its moisture in the open air, it is placed in a kiln and
fired. The first firing hardens the pottery, and it is then ready to be glazed and fired again.
For areas where they do not want any glaze, such as the bottom of the pot, artisans paint
on melted wax that will later burn off in the kiln. They then pour on the liquid glaze and let
it run over the clay surface, making any kind of decorative pattern that they want.
>62 Mimicry in Plants
Plant adaptations can be remarkably complex. Certain species of orchids, for instance,
imitate female bees, other plants look and smell like dead animals, and still others have the
appearance of stones. These strange adaptations to life represent just a few of the
sophisticated means by which plants enhance their chances of survival. Mimicry in plants
or animals is a three part system. There is a model: the animal, plant or substrate being
initiated. There is a mimic: the organism that imitates the model. And there is a signal
receiver or dupe: the animal that cannot effectively distinguish between the model and the
mimic. Mimetic traits may include morphological structures, color patterns, behaviors or
other attributes of the mimic that promote its resemblance to a model. That model may be
either an unrelated species or an inanimate object, such as the background against which an
organism spends most of its time. Mimicry is not an active strategy on the part of an
individual plant; flowers do not deliberately trick or deceive animals into visiting them.
Mimicry arises as the result of evolution through natural selection and the occurrence of
random genetic mutations that lead over many generations to the appearance of favorable
characteristics. If such traits help to camouflage a plant, for example, the plant is likely to
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have a survival advantage over other plants that are less well camouflaged. The plant will
leave more descendants, thereby passing the advantage to the next generation. For natural
selection to favor the evolution of mimicry, the mimicry must derive a reproductive
advantage from modeling itself after another organism or object: its fitness, measured as
the number of offspring produced that survive into the next generation, must be increased
as the result of deception.
>63 Oil and Water
To understand the emulsifying process, we must first accept the scientific principle that
oil and water do not naturally mix. Quite literally, they find each other's presence repulsive.
A good illustration of this aversion is homemade oil and vinegar salad dressing. When you
shake or beat your salad dressing, you do more than disperse the oil throughout the vinegar:
you also break down the oil into droplets minute enough to remain temporarily suspended
in the vinegar (which from now on we will call water, because that tart condiment is in
effect mainly water). The second you stop agitating the dressing, the oil droplets start to
combine into units too large to be suspended in the water, and thus slither their way upward,
separating from the water in the process. The oil rises to the top and the water sinks because
oil has a lower specific density than water. If you want a stable emulsion, you need an
emulsifying agent which prevents the oil droplets from combining into larger units.
Emulsifying agents occur naturally in many animal substances including egg yolks and
milk. An emulsifying agent helps to keep the oil particles from combining in three basic
ways. First, the agent coats the oil, serving as a physical barrier between the droplets. Second,
it reduces the water's surface tension, which, in turn, reduces the water's ability to repulse
oil. Third, the agent gives the surfaces of the oil droplets identical electrical charges; since
like charges repel each other the droplets repel each other.
>64 Salt and Metabolism
Just how salt became so crucial to our metabolism is a mystery; one appealing theory traces
our dependence on it to the chemistry of the late Cambrian seas. It was there, a half billion
years ago, that tiny metazoan organisms first evolved systems for sequestering and
circulating fluids. The water of the early oceans might thus have become the chemical
prototype for the fluids of all animal life - the medium in which cellular operations could
continue no matter how the external environment changed. This speculation is based on the
fact that, even today, the blood serums of radically divergent species are remarkably
similar. Lizards, platypuses, sheep, and humans could hardly be more different in anatomy
or eating habits, yet the salt content in the fluid surrounding their blood cells is virtually
identical. As early marine species made their way to fresh water and eventually to dry land,
sodium remained a key ingredient of their interior, if not their exterior, milieu. The most
successful mammalian species would have been those that developed efficient hormonal
systems for maintaining the needed sodium concentrations. The human body, for example,
uses the hormones renin, angiotensin, and aldosterone to retain or release tissue fluids and
blood plasma. The result, under favorable conditions, is a dynamic equilibrium in which
neither fluid volume nor sodium concentration fluctuates too dramatically. But if the body
is deprived of salt, the effects soon become dangerous, despite compensatory mechanisms.
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>65 The Early Settlers in North America
The North American frontier changed some of the characteristics of the pioneers of the
1750's and intensified others. They were, as a group, semiliterate, proud, and stubborn, as
dogged in their insistence on their own way of life as pine roots cracking granite to grow.
Perhaps their greatest resource was their capacity to endure. They outlasted recurrent
plagues of smallpox and malaria and a steady progression of natural accidents. They were
incredibly prolific. Squire Boone's family of eight children was small by frontier standards.
James Roberson, an eventual neighbor of Boone's and the founder of Nashville, had eleven
children. Twice married John Sevier, the first governor of Tennessee, fathered eighteen;
his longtime enemy, John Tipton, also twice married, produced seventeen. The entire assets
of one of these huge families often amounted, in the beginning, to little more than an axe, a
hunting knife, an auger, a rifle, a horse or two, some cattle and a few pigs, a sack of corn
seed and another of salt, perhaps a crosscut saw, and a loom. Those who moved first into a
new region lived for months at a time on wild meat, Indian maize, and native fruits in
season. Yet if they were poor at the beginning, they confidently expected that soon they
would be rich. In a way almost impossible to define to urban dwellers, a slice of ground
suitable for farming represented not just dollars and cents, but dignity. The obsession
brought shiploads of yearners every week to Boston, New York, Philadelphia, Baltimore,
Charles Towne, and Savannah. It sent them streaming westward into the wilderness after
their predecessors to raise still more children who wanted still more land.
>66 Plants in the Deserts
Some cacti, like the saguaro, grow to tree size, but true trees need more moisture than
most desert environments can supply, so they are scarce on deserts. Close to streambeds,
cottonwoods can sometimes be found. Though these streams are dry most of the year,
water flows there longest and is usually available fairly close to the surface. Elsewhere,
trees must send taproots deep into the hard baked desert soil to draw on underground
water. Perhaps the most widespread family of trees on the world's deserts is the acacia,
whose taproots drill down as far as 25 feet (7. 5 meters). The mesquite common on North
American deserts in both tree and shrub forms, does not begin to grow above ground until
its root system is completely developed, ensuring the plant a supply of moisture. The
roots of shrubs and trees help to hold the desert soil in place. Their stalks and branches also
act as screens to keep the wind from sweeping great drifts of sand along the surface. These
services are vital if a desert is to support life. Scientists estimate that a desert needs year
round plant cover over 20 to 40 percent of its surface. If shrubs are too far apart -
separated by a distance greater than five times their height - soil around them is likely to
blow away. Without the shelter of established shrubs, new seedlings will have difficulty in
getting a start. On the other hand, plants that are too close together may compete for
underground moisture. To protect themselves from this competition some shrubs give off
a substance that kills young plants that sprout too close to them. In addition to a few
varieties of trees and tough shrubs, most deserts have grasses, herbs, and other annual
plants. These do not compete for moisture with the longer lived growth. They spring up
quickly after rains, when the surface is moist. Then, for a brief time, the desert can be
literally carpeted with color. Almost as quickly as they appeared, these small plants die
away. But they have developed special ways of ensuring the life of another generation
when rains come again.
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> 6 7 T h e A me r i c a n C i v i l W a r
The military aspect of the United States Civil War has always attracted the most
attention from scholars. The roar of gunfire, the massed movements of uniformed men, the
shrill o f bugles, and the drama of hand to hand combat have fascinated students of warfare
for a century. Behind the lines, however, life was less spectacular. It was the story of back
breaking labor to provide the fighting men with food and arms, of nerve tingling
uncertainty about the course of national events, of heartbreak over sons or brothers or
husbands lost in battle. If the men on the firing line won the victories, the means to those
victories were forged on the home front. Never in the nation's history had Americans
worked harder for victory than in the Civil War. Northerners and Southerners alike threw
themselves into the task of supplying their respective armies. Both governments made
tremendous demands upon civilians and, in general, received willing cooperation. By 1863
the Northern war economy was rumbling along in high gear. Everything from steamboats
to shovels was needed and produced. Denied Southern cotton, textile mills turned to wool
for blankets and uniforms. Hides by the hundreds of thousands were turned into shoes and
harness and saddles; ironworks manufactured locomotives, ordnance, and armor plate.
Where private enterprise lagged, the government set up its own factories or arsenals.
Agriculture boomed, with machinery doing the job of farm workers drawn into the army. In
short, everything that a nation needed to fight a modern war was produced in uncounted
numbers. Inevitably there were profiteers with gold headed canes and flamboyant diamond
stickpins, but for every crooked tycoon there were thousands of ordinary citizens living on
fixed incomes who did their best to cope with rising prices and still make a contribution to
the war effort. Those who could buy war bonds: others knitted, sewed, nursed, or lent any
other assistance in their power.
>68 Women in Colonial North America
The status of women in colonial North America has been well studied and described
and can be briefly summarized. Throughout the colonial period there was a marked
shortage of women, which varied with the regions and was always greatest in the frontier
areas. This favorable ratio enhanced women's status and position and allowed them to
pursue different careers. The Puritans, the religious sect that dominated the early British
colonies in North America, regarded idleness as a sin, and believed that life in an
underdeveloped country made it absolutely necessary that each member of the community
perform an economic function. Thus work for women, married or single, was not only
approved, it was regarded as a civic duty. Puritan town councils expected widows and
unattached women to be self supporting and for a long time provided needy spinsters with
parcels of land. There was no social sanction against married women working; on the
contrary, wives were expected to help their husbands in their trade and won social approval
for doing extra work in or out of the home. Needy children, girls as well as boys, were
indentured or apprenticed and were expected to work for their keep. The vast majority of
women worked within their homes, where their labor produced most articles needed for the
family. The entire colonial production of cloth and clothing and partially that of shoes was
in the hands of women. In addition to these occupations, women were found in many
different kinds of employment. They were butchers, silversmiths, gunsmiths and
upholsterers. They ran mills, plantations, tanyards, shipyards, and every kind of shop,
39
tavern, and boardinghouse. They were gatekeepers, jail keepers, sextons, journalists,
printers, apothecaries, midwives, nurses, and teachers.
>69 The Revolution in American
Higher Education To produce the upheaval in the United States that changed and
modernized the domain of higher education from the mid 1860's to the mid 1880's, three
primary causes interacted. The emergence of a half dozen leaders in education provided the
personal force that was needed. Moreover, an outcry for a fresher, more practical, and more
advanced kind of instruction arose among the alumni and friends of nearly all of the old
colleges and grew into a movement that overrode all conservative opposition. The
aggressive "Young Yale" movement appeared, demanding partial alumni control, a more
liberal spirit, and a broader course of study. The graduates of Harvard College
simultaneously rallied to relieve the college's poverty and demand new enterprise.
Education was pushing toward higher standards in the East by throwing off church
leadership everywhere, and in the West by finding a wider range of studies and a new sense
of public duty. The old style classical education received its most crushing blow in the
citadel of Harvard College, where Dr. Charles Eliot, a young captain of thirty five, son of a
former treasurer of Harvard, led the progressive forces. Five revolutionary advances were
made during the first years of Dr. Eliot's administration. They were the elevation and
amplification of entrance requirements, the enlargement of the curriculum and the
development of the elective system, the recognition of graduate study in the liberal arts, the
raising of professional training in law, medicine, and engineering to a postgraduate level,
and the fostering of greater maturity in students' life. Standards of admission were sharply
advanced in 1872-1873 and 1876-1877. By the appointment of a dean to take charge of
student affairs, and a wise handling of discipline, the undergraduates were led to regard
themselves more as young gentlemen and less as young animals. One new course of study
after another was opened up - science, music, the history of the fine arts, advanced Spanish,
political economy, physics, classical philology, and international law.
>70 Garza's Art Works
Carmen Lomas Garza's eloquent etchings, lithographs, and gouache paintings depict
primal images of the rural environment and communal cultural experience of Mexican
descended people in the United States. In an introspective and personal language, she
describes the customs, traditions, and ways of life of her Texan Mexican heritage. By 1972,
Lomas Garza had evolved her distinctive monitos, paintings of stylized figures in culturally
specific social environments. She transposes images and scenes from her past, combining
cultural documentation with invention in an interplay of fact and fiction. Through selection,
emphasis, and creation, these monitos delineate facets of experience, expressing deeper
truths. Oral tradition is a mainstay of Chicano culture. In both urban and rural communities,
a rich and varied repertoire of ballads, tales, and poetic forms is preserved in memory and
passed from generation to generation. Lomas Garza's monitos function as an oral tradition
in visual form. Her unique art of storytelling employs iconographic elements to create a
concentrated narration. Visual episodes within an unfolding epic tale of cultural
regeneration, the monitos keep alive the customs and daily practices that give meaning and
coherence to Chicano identity. Their basic aim is to delight and instruct. For those outside
Chicano culture, the precise and minutely detail ed monitos provide a glimpse into the rich
40
and vibrant lifestyle of the largest Spanish speaking cultural group within the United States
society. Although her art has an innocent earnestness and folkloric affinity, Lomas Garza's
expression is neither naive nor instinctive. The artist is highly trained academically, but
has chosen to remain independent of dominant artistic trends in order to work toward a
private aesthetic response to social concerns. While her work does not posit an overt
political statement, it originates from a desire to respond to the contemporary situation of
Mexican Americans by expressing positive images of their culture.
>71 The Alaska Pipeline
The Alaska pipeline starts at the frozen edge of the Arctic Ocean. It stretches southward
across the largest and northernmost state in the United States, ending at a remote ice free
seaport village nearly 800 miles from where it begins. It is massive in size and extremely
complicated to operate. The steel pipe crosses windswept plains and endless miles of
delicate tundra that tops the frozen ground. It weaves through crooked canyons, climbs
sheer mountains, plunges over rocky crags, makes its way through thick forests, and passes
over or under hundreds of rivers and streams. The pipe is 4 feet in diameter, and up to 2
million barrels (or 84 million gallons) of crude oil can be pumped through it daily. Resting
on H shaped steel racks called "bents", long sections of the pipeline follow a zigzag course
high above the frozen earth. Other long sections drop out of sight beneath spongy or rocky
ground and return to the surface later on. The pattern of the pipeline's up and down route is
determined by the often harsh demands of the Arctic and sub arctic climate, the tortuous
lay of the land, and the varied compositions of soil, rock, or permafrost(permanently frozen
ground). A little more than half of the pipeline is elevated above the ground. The remainder
is buried anywhere from 3 to 12 feet, depending largely upon the type of terrain and the
properties of the soil. One of the largest in the world, the pipeline cost
8 approximately billion and is by far the biggest and most expensive construction project
ever undertaken by private industry. In fact, no single business could raise that much money,
so 8 major oil companies formed a consortium in order to share the costs. Each company
controlled oil rights to particular shares of land in the oil fields and paid into the pipeline
construction fund according to the size of its holdings. Today, despite enormous problems
of climate, supply shortages, equipment breakdowns, labor disagreements, treacherous
terrain, a certain amount of mismanagement, and even theft, the Alaska pipeline has been
completed and is operating.
>72 The Satiric Literature
Perhaps the most striking quality of satiric literature is its freshness, its originality of
perspective. Satire rarely offers original ideas. Instead, it presents the familiar in a new
form. Satirists do not offer the world new philosophies. What they do is to look at familiar
conditions from a perspective that makes these conditions seem foolish, harmful, or
affected. Satire jars us out of complacence into a pleasantly shocked realization that many
of the values we unquestioningly accept are false. Don Quixote derides the stupidity of
knights Brave New World ridicules the pretensions of science; A Modest Proposal
dramatizes starvation by advocating cannibalism. None of these ideas is original. Chivalry
was suspect before Cervantes, humanists objected to the claims of pure science before
Aldous Huxley, and people were aware of famine before Swift. It was not the originality of
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the idea that made these satires popular. It was the manner of expression, the satiric method
that made them interesting and entertaining. Satires are read because they are aesthetically
satisfying works of art, not because they are morally wholesome or ethically instructive.
They are stimulating and refreshing because with commonsense briskness they brush away
illusions and secondhand opinions. With spontaneous irreverence, satire rearranges
perspectives, scrambles familiar objects into incongruous juxtaposition, and speaks in a
personal idiom instead of abstract platitude.
Satire exists because there is need for it. It has lived because readers appreciate a
refreshing stimulus, an irreverent reminder that they live in a world of platitudinous
thinking, cheap moralizing, and foolish philosophy. Satire serves to prod people into an
awareness of truth, though rarely to any action on behalf of truth. Satire tends to remind
people that much of what they see, hear, and read in popular media is sanctimonious,
sentimental, and only partially true. Life resembles in only a slight degree the popular
image of it. Soldiers rarely hold the ideals that movies attribute to them, nor do ordinary
citizens devote their lives to unselfish service of humanity. Intelligent people know these
things but tend to forget them when they do not hear them expressed.
>73 The Microscopic Technique
Each advance in microscopic technique has provided scientists with new perspectives
on the function of living organisms and the nature of matter itself. The invention of the
visible light microscope late in the sixteenth century introduced a previously unknown
realm of single celled plants and animals. In the twentieth century, electron microscopes
have provided direct views of x viruses and minuscule surface structures. Now another
type of microscope, one that utilizes rays rather than light or electrons, offers a different
way of examining tiny details; it should extend human perception still farther into the
natural world. The dream of building an x ray microscope dates to back 1895; its
development, however was virtually halted in the 1940's because the development of the
electron microscope was progressing rapidly. During the 1940's, electron microscopes
routinely achieved resolution better than that possible with a visible light microscope,
while the performance of x ray microscopes resisted improvement. In recent years,
however, interest in x ray microscopes has revived, largely because of advances such as the
development of new sources of x ray illumination. As a result, the brightness available
today is millions of times that of x ray tubes, which, for most of the century, were the only
available sources of soft x rays. The new x ray microscopes considerably improve on the
resolution provided by optical microscopes. They can also be used to map the distribution
of certain chemical elements. Some can form pictures in extremely short times; others hold
the promise of special capabilities such as three dimensional imaging. Unlike conventional
electron microscope, x ray microscope enables specimens to be kept in air and in water,
which means that biological samples can be studied under conditions similar to their
natural state. The illumination used, so called soft x rays in the wavelength range of twenty
to forty angstroms (an angstrom is one ten billionth of a meter), is also sufficiently
penetrating to image intact biological cells in many cases. Because of the wavelength of the
x rays used, soft x ray microscopes will never match the highest resolution possible with
electron microscopes. Rather, their special properties will make possible investigations
that will complement those performed with light and electron based instruments.
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>74 The History of Chemistry
Chemistry did not emerge as a science until after the scientific revolution in the
seventeenth century and then only rather slowly and laboriously. But chemical
knowledge is as old as history, being almost entirely concerned with the practical arts
of living. Cooking is essentially a chemical process; so is the melting of metals and
the administration of drugs and poisons. This basic chemical knowledge, which was
applied in most cases as a rule of thumb, was nevertheless dependent on previous
experiment. It also served to stimulate a fundamental curiosity about the processes
themselves. New information was always being gained as artisans improved
techniques to gain better results. The development of a scientific approach to
chemistry was, however, hampered by several factors. The most serious problem
was the vast range of material available and the consequent difficulty of organizing it
into some system. In addition, there were social and intellectual difficulties,
chemistry is nothing if not practical; those who practice it must use their hands, they
must have a certain practical flair. Yet in many ancient civilizations, practical tasks
were primarily the province of a slave population. The thinker or philosopher stood
apart from this mundane world, where the practical arts appeared to lack any
intellectual content or interest. The final problem for early chemical science was the
element of secrecy. Experts in specific trades had developed their own techniques and
guarded their knowledge to prevent others from stealing their livelihood. Another
factor that contributed to secrecy was the esoteric nature of the knowledge of a
alchemists, who were trying to transform base metals into gold or were concerned
with the hunt for the elixir that would bestow the blessing of eternal life. In one sense,
the second of these was the more serious impediment because the records of the
chemical processes that early alchemists had discovered were often written down in
symbolic language intelligible to very few or in symbols that were purposely
obscure.
>75 Hydrogen and Industries
Hydrogen, the lightest and simplest of the elements, has several properties that
make it valuable for many industries. It releases more heat per unit of weight than any
other fuel. In rocket engines, tons of hydrogen and oxygen are burned, and hydrogen
is used with oxygen for welding torches that produce temperatures as high as 4, 000
degrees F and can be used in cutting steel. Fuel cells to generate electricity operate on
hydrogen and oxygen.
Hydrogen also serves to prevent metals from tarnishing during heat treatments by
removing the oxygen from them. Although it would be difficult to remove the oxygen
by itself, hydrogen readily combines with oxygen to form water, which can be heated
to steam and easily removed.
Hydrogen is also useful in the food industry for a process know as hydrogenation.
Products such as margarine and cooking oils are changed from liquids to semisolids
by adding hydrogen to their molecules. Soap manufacturers also use hydrogen for this
purpose.
Hydrogen is also one of the coolest refrigerants. It does not become a liquid until
it reaches temperatures of -425 degrees F. Pure hydrogen gas is used in large electric
43
generators to cool the coils. In addition, in the chemical industry, hydrogen is used to
produce ammonia, gasoline, methyl alcohol, and many other important products.
>76 MARS
Mars According to the best evidence gathered by space probes and astronomers, Mars
is an inhospitable planet, more similar to Earth's Moon than to Earth itself - a dry,
stark, seemingly lifeless world. Mars' air pressure is equal to Earth's at an altitude of
100,000 feet. The air there is 95% carbon dioxide. Mars has no ozone layer to screen
out the Sun's lethal radiation. Daytime temperatures may reach above freezing, but
because the planet is blanketed by the mere wisp of an atmosphere, the heat radiates
back into space. Even at the equator, the temperature drops to 50(60) at night. Today
there is no liquid water, although valleys and channels on the surface show evidence
of having been carved by running water. The polar ice caps are made of frozen water
and carbon dioxide, and water may be frozen in the ground as permafrost. Despite
these difficult conditions, certain scientists believe that there is a possibility of
transforming Mars into a more Earth like planet. Nuclear reactors might be used to
melt frozen gases and eventually build up the atmosphere. This in turn could create a
"greenhouse effect" that would stop heat from radiating back into space. Liquid water
could be thawed to form a polar ocean. Once enough ice has melted, suitable plants
could be introduced to build up the level of oxygen in the atmosphere so that, in time,
the planet would support animal life from Earth and even permanent human colonies.
"This was once thought to be so far in the future as to be irrelevant," said Christopher
McKay, a research scientist at the National Aeronautics and Space Administration.
"But now it's starting to look practical. We could begin work in four or five decades."
The idea of "terra forming" Mars, as enthusiasts call it, has its roots in science fiction.
But as researchers develop a more profound understanding of how Earth's ecology
supports life, they have begun to see how it may be possible to create similar
conditions on Mars. Don't plan on homesteading on Mars any time soon, though. The
process could take hundreds or even thousands of years to complete, and the cost
would be staggering.
>77 Food and Health
The food we eat seems to have profound effects on our health. Although science
has made enormous steps in making food more fit to eat, it has, at the same time, made
many foods unfit to eat. Some research has shown that perhaps eighty percent of all
human illnesses are related to diet and forty percent of cancer is related to the diet as
well, especially cancer of the colon. Different cultures are more prone to contract
certain illnesses because of the food that is characteristic in these cultures. That food
is related to illness is not a new discovery. In 1945, government researchers realized
that nitrates and nitrites, commonly used to preserve color in meats, and other food
additives, caused cancer. Yet, these carcinogenic additives remain in our food, and it
becomes more difficult all the time to know which things in the packaging labels of
processed food are helpful or harmful. The additives which we eat are not all so direct.
Farmers often give penicillin to beef and poultry, and because of this, penicillin has
been found in the milk of treated cows. Sometimes similar drugs are administered
to animals not for medicinal purposes, but for financial reasons. The farmers are
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simply trying to fatten the animals in order to obtain a higher price on the market.
Although the Food and Drug Administration (FDA) has tried repeatedly to control
these procedures, the practices continue.
>78 Police and Communities
Few institutions are more important to an urban community than its police, yet
there are few subjects historians know so little about. Most of the early academic
interests developed among political scientists and sociologists, who usually
examined their own contemporary problems with only a nod toward the past. Even
the public seemed concerned only during crime waves, periods of blatant
corruption, or after a particularly grisly episode. Party regulars and reformers
generally viewed the institution from a political perspective; newspapers and
magazines - the nineteenth century's media - emphasized the vivid and spectacular.
Yet urban society has always vested a wide, indeed awesome, responsibility in its
police. Not only were they to maintain order, prevent crime, and protect life and
property, but historically they were also to fight fires, suppress vice, assist in health
services, supervise elections, direct traffic, inspect buildings, and locate truants and
runaways. In addition, it was assumed that the police were the special guardians of
the citizens' liberties and the community's tranquility. Of course, the performance
never matched expectations. The record contains some success, but mostly failure;
some effective leadership, but largely official incompetence and betrayal. The
notion of a professional police force in America is a creation of the twentieth
century; not until our own times have cities begun to take the steps necessary to
produce modern departments.
>79 Population Growth
The growth of population during the past few centuries is no proof that
population will continue to grow straight upward toward infinity and doom. On the
contrary, demographic history offers evidence that population growth has not been at
all constant. According to paleoecologist Edward Deevey, the past million years
show three momentous changes. The first, a rapid increase in population around one
million B. C., followed the innovations of tool making and tool using. But when the
new power from the use of tools has been exploited, the rate of world population
growth fell and became almost stable. The next rapid jump in population started
perhaps 10,000 years ago, when mankind began to keep herds, plow and plant the
earth. Once again when initial productivity gains had been absorbed, the rate of
population growth abated. These two episodes suggest that the third great change, the
present rapid growth, which began in the West between 250 and 350 years ago, may
also slow down when, or if, technology begins to yield fewer innovations. Of course,
the current knowledge revolution may continue without foreseeable end. Either way
- contrary to popular belief in constant geometric growth - population can be expected
in the long run to adjust to productivity. And when one takes this view, population
growth is seen to represent economic progress and human triumph rather than social
failure.
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>80 Evolution and Wheels
In the past, evolutionary biologists contemplating the absence of wheels in nature
agreed that the explanation was not undesirability: wheels would be good for animals,
just as they are for us. Animals were prevented from evolving wheels, the biologists
reasoned, by the following dilemma: living cells in an animal's body are connected to
the heart by blood vessels and to the brain by nerves. Because a rotating joint is
essential to a wheel, a wheel made of living cells would twist its artery vein and
nerve connections at the first revolution, making living impracticable.
However, there is a flaw in the argument that the evolution of wheeled animals
was thwarted by the insoluble joint problem. The theory fails to explain why animals
have not evolved wheels of dead tissue with no need for arteries and nerves. Countless
animals, including us, bear external structures without blood supply or nerves - for
example, our hair and fingernails, or the scales, claws, and horns of other animals.
Why have rats not evolved bony wheels, similar to roller skates? Paws might be more
useful than wheels in some situations, but cats' claws are retractable: why not
retractable wheels? We thus arrive at the serious biological paradox flippantly termed
the RRR dilemma: nature's failure to produce rats with retractable roller skates.